St. Peter's Basilica

Overview

St. Peter's is a church built in the Renaissance style located in the Vatican City west of the River Tiber and near the Janiculum Hill and Hadrian's Mausoleum. Its central dome dominates the skyline of Rome. The basilica is approached via St. Peter's Square, a forecourt in two sections, both surrounded by tall colonnades. The first space is oval and the second trapezoidal. The façade of the basilica, with a giant order of columns, stretches across the end of the square and is approached by steps on which stand two 5.55-metre (18.2 ft) statues of the first-century apostles to Rome, Saints Peter and Paul.

The basilica is cruciform in shape, with an elongated nave in the Latin cross form but the early designs were for a centrally planned structure and this is still in evidence in the architecture. The central space is dominated both externally and internally by one of the largest domes in the world. Set into the niches of the dome's four gargantuan support piers are colossal statues representing the four major holy relics believed to be held in the basilica: St. Longinus with his spear, St. Helena with the True Cross, St. Veronica with her veil, and St. Andrew, whose skull was possessed by the Vatican until the 20th century. The entrance is through a narthex, or entrance hall, which stretches across the building. One of the decorated bronze doors leading from the narthex is the Holy Door, opened only during jubilees.

The interior dimensions are vast when compared to other churches. One author wrote: "Only gradually does it dawn upon us – as we watch people draw near to this or that monument, strangely they appear to shrink; they are, of course, dwarfed by the scale of everything in the building. This in its turn overwhelms us."

The nave which leads to the central dome is in three bays, with piers supporting a barrel vault, the highest of any church. The nave is framed by wide aisles which have a number of chapels off them. There are also chapels surrounding the dome. Moving around the basilica in a clockwise direction they are: The Baptistery, the Chapel of the Presentation of the Virgin, the larger Choir Chapel, the altar of the Transfiguration, the Clementine Chapel with the altar of Saint Gregory, the Sacristy Entrance, the Altar of the Lie, the left transept with altars to the Crucifixion of Saint Peter, Saint Joseph and Saint Thomas, the altar of the Sacred Heart, the Chapel of the Madonna of Column, the altar of Saint Peter and the Paralytic, the apse with the Chair of Saint Peter, the altar of Saint Peter raising Tabitha, the altar of St. Petronilla, the altar of the Archangel Michael, the altar of the Navicella, the right transept with altars of Saint Erasmus, Saints Processo and Martiniano, and Saint Wenceslas, the altar of St. Jerome, the altar of Saint Basil, the Gregorian Chapel with the altar of the Madonna of Succour, the larger Chapel of the Holy Sacrament, the Chapel of Saint Sebastian and the Chapel of the Pietà. The Monuments, in a clockwise direction, are to: Maria Clementina Sobieska, The Stuarts, Benedict XV, John XXIII, St. Pius X, Innocent VIII, Leo XI, Innocent XI, Pius VII, Pius VIII, Alexander VII, Alexander VIII, Paul III, Urban VIII, Clement X, Clement XIII, Benedict XIV, St Peter (Bronze Statue), Gregory XVI, Gregory XIV, Gregory XIII, Matilda of Canossa, Innocent XII, Pius XII, Pius XI, Christina of Sweden, and Leo XII.

Status

St. Peter's Basilica is one of the papal basilicas (previously styled "patriarchal basilicas") and one of the four Major Basilicas of Rome the others (all of which are also Papal Basilicas) being the Basilicas of St. John Lateran, St. Mary Major, and St. Paul outside the Walls. The rank of major basilica confers on St. Peter's Basilica precedence before all minor basilicas worldwide. However, unlike all the other Papal Major Basilicas, it is wholly within the territory, and thus the sovereign jurisdiction, of the Vatican City State, and not that of Italy.

It is the most prominent building in the Vatican City. Its dome is a feature of the skyline of Rome and covers an area of 0.139 hectares (0.34 acres). One of the holiest sites of Christianity and Catholic Tradition, it is traditionally the burial site of its titular, St. Peter, who was the head of the twelve Apostles of Jesus and, according to tradition, the first Bishop of Antioch and later the first Bishop of Rome, rendering him the first Pope. Although the New Testament does not mention St. Peter's martyrdom in Rome, tradition, based on the writings of the Fathers of the Church, holds that his tomb is below the baldachin and the altar of the Basilica in the "Confession". For this reason, many Popes have, from the early years of the Church, been buried near Pope St. Peter in the necropolis beneath the Basilica. Construction of the current basilica, over the old Constantinian basilica, began on 18 April 1506 and finished in 1615. At length, on 18 November 1626 Pope Urban VIII solemnly dedicated the Basilica.

St. Peter's Basilica is neither the Pope's official seat nor first in rank among the Major Basilicas of Rome. This honour is held by the Pope's cathedral, the Archbasilica of St. John Lateran, the mother church of all churches in communion with the Catholic Church. However, St. Peter's is functionally the Pope's principal church, as most Papal liturgies and ceremonies take place there due to its size, proximity to the Papal residence, and location within the Vatican City proper. The "Chair of Saint Peter", or cathedra, an ancient chair sometimes presumed to have been used by St. Peter himself, but which was a gift from Charles the Bald and used by many popes, symbolizes the continuing line of apostolic succession from St. Peter to the reigning Pope. It occupies an elevated position in the apse of the Basilica, supported symbolically by the Doctors of the Church and enlightened symbolically by the Holy Spirit.

As one of the constituent structures of the historically and architecturally significant Vatican City, St. Peter's Basilica was inscribed as a UNESCO World Heritage Site in 1984 under criteria (i), (ii), (iv), and (vi). With an exterior area of 21,095 square metres (227,060 ft2), an interior area of 15,160 square metres (163,200 ft2), St. Peter's Basilica is the largest Christian church building in the world by the two latter metrics and the second largest by the first as of 2016. The top of its dome, at 448.1 feet (136.6 m), also places it as the second tallest building in Rome as of 2016. The dome's soaring height placed it among the tallest buildings of the Old World, and it continues to hold the title of tallest dome in the world. Though the largest dome in the world by diameter at the time of its completion, it no longer holds this distinction.

History

Saint Peter's burial site

After the crucifixion of Jesus, it is recorded in the Biblical book of the Acts of the Apostles that one of his twelve disciples, Simon known as Saint Peter, a fisherman from Galilee, took a leadership position among Jesus' followers and was of great importance in the founding of the Christian Church. The name Peter is "Petrus" in Latin and "Petros" in Greek, deriving from petra which means "stone" or "rock" in Greek, and is the literal translation of the Aramaic "Kepa", the name given to Simon by Jesus. (John 1:42, and see Matthew 16:18)

Catholic tradition holds that Peter, after a ministry of thirty-four years, travelled to Rome and met his martyrdom there along with Paul on 13 October 64 AD during the reign of the Roman Emperor Nero. His execution was one of the many martyrdoms of Christians following the Great Fire of Rome. According to Jerome, Peter was crucified head downwards, by his own request because he considered himself unworthy to die in the same manner as Jesus. The crucifixion took place near an ancient Egyptian obelisk in the Circus of Nero. The obelisk now stands in St. Peter's Square and is revered as a "witness" to Peter's death. It is one of several ancient Obelisks of Rome.

According to tradition, Peter's remains were buried just outside the Circus, on the Mons Vaticanus across the Via Cornelia from the Circus, less than 150 metres (490 ft) from his place of death. The Via Cornelia was a road which ran east-to-west along the north wall of the Circus on land now covered by the southern portions of the Basilica and St. Peter's Square. A shrine was built on this site some years later. Almost three hundred years later, Old St. Peter's Basilica was constructed over this site.

The area now covered by the Vatican City had been a cemetery for some years before the Circus of Nero was built. It was a burial ground for the numerous executions in the Circus and contained many Christian burials as for many years after the burial of Saint Peter, many Christians chose to be buried near him.

In 1939, in the reign of Pope Pius XII, 10 years of archaeological research began under the crypt of the basilica in an area inaccessible since the ninth century. The excavations revealed the remains of shrines of different periods at different levels, from Clement VIII (1594) to Callixtus II (1123) and Gregory I (590–604), built over an aedicula containing fragments of bones that were folded in a tissue with gold decorations, tinted with the precious murex purple. Although it could not be determined with certainty that the bones were those of Peter, the rare vestments suggested a burial of great importance. On 23 December 1950, in his pre-Christmas radio broadcast to the world, Pope Pius XII announced the discovery of Saint Peter's tomb.

Old St. Peter's Basilica

Old St. Peter's Basilica was the fourth-century church begun by the Emperor Constantine the Great between 319 and 333 AD. It was of typical basilical form, a wide nave and two aisles on each side and an apsidal end, with the addition of a transept or bema, giving the building the shape of a tau cross. It was over 103.6 metres (340 ft) long, and the entrance was preceded by a large colonnaded atrium. This church had been built over the small shrine believed to mark the burial place of St. Peter, though the tomb was "smashed" in 846 AD. It contained a very large number of burials and memorials, including those of most of the popes from St. Peter to the 15th century. Like all of the earliest churches in Rome, both this church and its successor had the entrance to the east and the apse at the west end of the building. Since the construction of the current basilica, the name Old St. Peter's Basilica has been used for its predecessor to distinguish the two buildings.

Plan to rebuild

By the end of the 15th century, having been neglected during the period of the Avignon Papacy, the old basilica had fallen into disrepair. It appears that the first pope to consider rebuilding or at least making radical changes was Pope Nicholas V (1447–1455). He commissioned work on the old building from Leone Battista Alberti and Bernardo Rossellino and also had Rossellino design a plan for an entirely new basilica, or an extreme modification of the old. His reign was frustrated by political problems and when he died, little had been achieved. He had, however, ordered the demolition of the Colosseum and by the time of his death, 2,522 cartloads of stone had been transported for use in the new building. The foundations were completed for a new transept and choir to form a domed Latin cross with the preserved nave and side aisles of the old basilica. Some walls for the choir had also been built.

Pope Julius II planned far more for St Peter's than Nicholas V's program of repair or modification. Julius was at that time planning his own tomb, which was to be designed and adorned with sculpture by Michelangelo and placed within St Peter's. In 1505 Julius made a decision to demolish the ancient basilica and replace it with a monumental structure to house his enormous tomb and "aggrandize himself in the popular imagination". A competition was held, and a number of the designs have survived at the Uffizi Gallery. A succession of popes and architects followed in the next 120 years, their combined efforts resulting in the present building. The scheme begun by Julius II continued through the reigns of Leo X (1513–1521), Adrian VI (1522–1523), Clement VII (1523–1534), Paul III (1534–1549), Julius III (1550–1555), Marcellus II (1555), Paul IV (1555–1559), Pius IV (1559–1565), Pius V (saint) (1565–1572), Gregory XIII (1572–1585), Sixtus V (1585–1590), Urban VII (1590), Gregory XIV (1590–1591), Innocent IX (1591), Clement VIII (1592–1605), Leo XI (1605), Paul V (1605–1621), Gregory XV (1621–1623), Urban VIII (1623–1644) and Innocent X (1644–1655).

Financing with indulgences

One method employed to finance the building of St. Peter's Basilica was the granting of indulgences in return for contributions. A major promoter of this method of fund-raising was Albrecht, Archbishop of Mainz and Magdeburg, who had to clear debts owed to the Roman Curia by contributing to the rebuilding program. To facilitate this, he appointed the German Dominican preacher Johann Tetzel, whose salesmanship provoked a scandal and led to the Protestant Reformation.

Digital copies

In the 2020s, the Vatican began seeking to use digital recreations of the Basilica in order to enhance education and allow people to experience it without needing to visit in person. In 2024, the Vatican partnered with Microsoft to create an interactive 3D model of the Basilica. The model was generated with artificial intelligence using over 400,000 high-resolution photographs taken by drones. Microsoft president Brad Smith described the project as "one of the most technologically advanced and sophisticated projects of its kind that has ever been pursued". The Vatican further collaborated with Microsoft in 2025 through the creation of another interactive version of the Basilica, this time recreated in the video game Minecraft. The Minecraft map, titled "Peter is Here", was developed as part of the 2025 Jubilee with the goal of engaging young audiences.

Architecture

Successive plans

Pope Julius's scheme for the grandest building in Christendom was the subject of a competition for which a number of entries remain intact in the Uffizi Gallery, Florence. It was the design of Donato Bramante that was selected, and for which the foundation stone was laid in 1506. This plan was in the form of an enormous Greek cross with a dome inspired by that of the huge circular Roman temple, the Pantheon. The main difference between Bramante's design and that of the Pantheon is that where the dome of the Pantheon is supported by a continuous wall, that of the new basilica was to be supported only on four large piers. This feature was maintained in the ultimate design. Bramante's dome was to be surmounted by a lantern with its own small dome but otherwise very similar in form to the Early Renaissance lantern of Florence Cathedral designed for Brunelleschi's dome by Michelozzo.

Bramante had envisioned that the central dome would be surrounded by four lower domes at the diagonal axes. The equal chancel, nave and transept arms were each to be of two bays ending in an apse. At each corner of the building was to stand a tower, so that the overall plan was square, with the apses projecting at the cardinal points. Each apse had two large radial buttresses, which squared off its semi-circular shape.

When Pope Julius died in 1513, Bramante was replaced with Giuliano da Sangallo and Fra Giocondo, who both died in 1515 (Bramante himself having died the previous year). Raphael was confirmed as the architect of St. Peter's on 1 August 1514. The main change in his plan is the nave of five bays, with a row of complex apsidal chapels off the aisles on either side. Raphael's plan for the chancel and transepts made the squareness of the exterior walls more definite by reducing the size of the towers, and the semi-circular apses more clearly defined by encircling each with an ambulatory.

In 1520 Raphael also died, aged 37, and his successor Baldassare Peruzzi maintained changes that Raphael had proposed to the internal arrangement of the three main apses, but otherwise reverted to the Greek cross plan and other features of Bramante. This plan did not go ahead because of various difficulties of both Church and state. In 1527 Rome was sacked and plundered by Emperor Charles V. Peruzzi died in 1536 without his plan being realized.

At this point Antonio da Sangallo the Younger submitted a plan which combines features of Peruzzi, Raphael and Bramante in its design and extends the building into a short nave with a wide façade and portico of dynamic projection. His proposal for the dome was much more elaborate in both structure and decoration than that of Bramante and included ribs on the exterior. Like Bramante, Sangallo proposed that the dome be surmounted by a lantern which he redesigned to a larger and much more elaborate form. Sangallo's main practical contribution was to strengthen Bramante's piers, which had begun to crack.

Michelangelo's contribution

Michelangelo took over a building site at which four piers, enormous beyond any constructed since ancient Roman times, were rising behind the remaining nave of the old basilica. He also inherited the numerous schemes designed and redesigned by some of the greatest architectural and engineering minds of the 16th century. There were certain common elements in these schemes. They all called for a dome to equal that engineered by Brunelleschi a century earlier and which has since dominated the skyline of Renaissance Florence, and they all called for a strongly symmetrical plan of either Greek Cross form, like the iconic St. Mark's Basilica in Venice, or of a Latin Cross with the transepts of identical form to the chancel, as at Florence Cathedral.

Even though the work had progressed only a little in 40 years, Michelangelo did not simply dismiss the ideas of the previous architects. He drew on them in developing a grand vision. Above all, Michelangelo recognized the essential quality of Bramante's original design. He reverted to the Greek Cross and, as Helen Gardner expresses it: "Without destroying the centralising features of Bramante's plan, Michelangelo, with a few strokes of the pen converted its snowflake complexity into massive, cohesive unity."

As it stands today, St. Peter's has been extended with a nave by Carlo Maderno. It is the chancel end (the ecclesiastical "Eastern end") with its huge centrally placed dome that is the work of Michelangelo. Because of its location within the Vatican State and because the projection of the nave screens the dome from sight when the building is approached from the square in front of it, the work of Michelangelo is best appreciated from a distance. What becomes apparent is that the architect has greatly reduced the clearly defined geometric forms of Bramante's plan of a square with square projections, and also of Raphael's plan of a square with semi-circular projections. Michelangelo has blurred the definition of the geometry by making the external masonry of massive proportions and filling in every corner with a small vestry or stairwell. The effect created is of a continuous wall surface that is folded or fractured at different angles, but lacks the right angles which usually define change of direction at the corners of a building. This exterior is surrounded by a giant order of Corinthian pilasters all set at slightly different angles to each other, in keeping with the ever-changing angles of the wall's surface. Above them, the huge cornice ripples in a continuous band, giving the appearance of keeping the whole building in a state of compression.

Dome: successive and final designs

The dome of St. Peter's rises to a total height of 136.57 metres (448.1 ft) from the floor of the basilica to the top of the external cross. It is the tallest dome in the world. Its internal diameter is 41.47 metres (136.1 ft), slightly smaller than two of the three other huge domes that preceded it, those of the Pantheon of Ancient Rome, 43.3 metres (142 ft), and Florence Cathedral of the Early Renaissance, 44 metres (144 ft). It has a greater diameter by approximately 30 feet (9.1 m) than Constantinople's Hagia Sophia church, completed in 537. It was to the domes of the Pantheon and Florence duomo that the architects of St. Peter's looked for solutions as to how to go about building what was conceived, from the outset, as the greatest dome of Christendom.

The dome of the Pantheon stands on a circular wall with no entrances or windows except a single door. The whole building is as high as it is wide. Its dome is constructed in a single shell of concrete, made light by the inclusion of a large amount of the volcanic stones tuff and pumice. The inner surface of the dome is deeply coffered which has the effect of creating both vertical and horizontal ribs while lightening the overall load. At the summit is an ocular opening 8 metres (26 ft) across which provides light to the interior.

Bramante's plan for the dome of St. Peter's (1506) follows that of the Pantheon very closely, and like that of the Pantheon, was designed to be constructed in Tufa Concrete for which he had rediscovered a formula. With the exception of the lantern that surmounts it, the profile is very similar, except that in this case, the supporting wall becomes a drum raised high above ground level on four massive piers. The solid wall, as used at the Pantheon, is lightened at St. Peter's by Bramante piercing it with windows and encircling it with a peristyle.

In the case of Florence Cathedral, the desired visual appearance of the pointed dome existed for many years before Brunelleschi made its construction feasible. Its double-shell construction of bricks locked together in a herringbone pattern (re-introduced from Byzantine architecture), and the gentle upward slope of its eight stone ribs made it possible for the construction to take place without the massive wooden formwork necessary to construct hemispherical arches. While its appearance, with the exception of the details of the lantern, is entirely Gothic, its engineering was highly innovative, and the product of a mind that had studied the huge vaults and remaining dome of Ancient Rome.

Addition of nave and facade

On 18 February 1606, under Pope Paul V, the dismantling of the remaining parts of the Constantinian basilica began. The marble cross that had been set at the top of the pediment by Pope Sylvester and Constantine the Great was lowered to the ground. The timbers were salvaged for the roof of the Borghese Palace and two rare black marble columns, the largest of their kind, were carefully stored and later used in the narthex. The tombs of various popes were opened, treasures removed and plans made for re-interment in the new basilica. The Pope had appointed Carlo Maderno in 1602. He was a nephew of Domenico Fontana and had demonstrated himself as a dynamic architect. Maderno's idea was to ring Michelangelo's building with chapels, but the Pope was hesitant about deviating from the master's plan, even though he had been dead for forty years. The Fabbrica or building committee, a group drawn from various nationalities and generally despised by the Curia who viewed the basilica as belonging to Rome rather than Christendom, were in a quandary as to how the building should proceed. One of the matters that influenced their thinking was the Counter-Reformation which increasingly associated a Greek Cross plan with paganism and saw the Latin Cross as truly symbolic of Christianity. The central plan also did not have a "dominant orientation toward the east."

Another influence on the thinking of both the Fabbrica and the Curia was a certain guilt at the demolition of the ancient building. The ground on which it and its various associated chapels, vestries and sacristies had stood for so long was hallowed. The only solution was to build a nave that encompassed the whole space. In 1607 a committee of ten architects was called together, and a decision was made to extend Michelangelo's building into a nave. Maderno's plans for both the nave and the facade were accepted.

The building of the nave began on 7 May 1607, and proceeded at a great rate, with an army of 700 labourers being employed. The following year, the façade was begun, in December 1614 the final touches were added to the stucco decoration of the vault and early in 1615 the partition wall between the two sections was pulled down. All the rubble was carted away, and the nave was ready for use by Palm Sunday.

The facade designed by Maderno, is 114.69 metres (376.3 ft) wide and 45.55 metres (149.4 ft) high and is built of travertine stone, with a giant order of Corinthian columns and a central pediment rising in front of a tall attic surmounted by thirteen statues: Christ flanked by eleven of the Apostles (except Saint Peter, whose statue is left of the stairs) and John the Baptist. The inscription below the cornice on the 1 metre (3.3 ft) tall frieze reads:

Influence on church architecture

The design of St. Peter's Basilica, and in particular its dome, has greatly influenced church architecture in Western Christendom. Within Rome, the huge domed church of Sant'Andrea della Valle was designed by Giacomo della Porta before the completion of St Peter's Basilica, and subsequently worked on by Carlo Maderno. This was followed by the domes of San Carlo ai Catinari, Sant'Agnese in Agone, and many others. Christopher Wren's dome at St Paul's Cathedral (London, England), the domes of Karlskirche (Vienna, Austria), St. Nicholas Church (Prague, Czech Republic), and the Pantheon (Paris, France) all pay homage to St Peter's Basilica.

The 19th and early-20th-century architectural revivals brought about the building of a great number of churches that imitate elements of St Peter's to a greater or lesser degree, including St. Mary of the Angels in Chicago, St. Josaphat's Basilica in Milwaukee, Immaculate Heart of Mary in Pittsburgh and Mary, Queen of the World Cathedral in Montreal, which replicates many aspects of St Peter's on a smaller scale. Postmodernism has seen free adaptations of St Peter's in the Basilica of Our Lady of Licheń, and the Basilica of Our Lady of Peace of Yamoussoukro.

Bernini's furnishings

Pope Urban VIII and Bernini

As a young boy Gian Lorenzo Bernini (1598–1680) visited St. Peter's with the painter Annibale Carracci and stated his wish to build "a mighty throne for the apostle". His wish came true. As a young man, in 1626, he received the patronage of Pope Urban VIII and worked on the embellishment of the Basilica for 50 years. Appointed as Maderno's successor in 1629, he was to become regarded as the greatest architect and sculptor of the Baroque period. Bernini's works at St. Peter's include the baldachin (baldaquin, from Italian: baldacchino), the Chapel of the Sacrament, the plan for the niches and loggias in the piers of the dome and the chair of St. Peter.

Bernini's first work at St. Peter's was to design the baldacchino, a pavilion-like structure 28.74 metres (94.3 ft) tall and claimed to be the largest piece of bronze in the world, which stands beneath the dome and above the altar. Its design is based on the ciborium, of which there are many in the churches of Rome, serving to create a sort of holy space above and around the altar on which the Sacrament is laid for the Eucharist and emphasizing the significance of this ritual. These ciboria are generally of white marble, with inlaid coloured stone. Bernini's concept was for something very different. He took his inspiration in part from the baldachin or canopy carried above the head of the pope in processions, and in part from eight ancient columns that had formed part of a screen in the old basilica. Their twisted barley-sugar shape had a special significance as they were modelled on those of the Temple of Jerusalem and donated by the Emperor Constantine. Based on these columns, Bernini created four huge columns of bronze, twisted and decorated with laurel leaves and bees, which were the emblem of Pope Urban.

The baldacchino is surmounted not with an architectural pediment, like most baldacchini, but with curved Baroque brackets supporting a draped canopy, like the brocade canopies carried in processions above precious iconic images. In this case, the draped canopy is of bronze, and all the details, including the olive leaves, bees, and the portrait heads of Urban's niece in childbirth and her newborn son, are picked out in gold leaf. The baldacchino stands as a vast free-standing sculptural object, central to and framed by the largest space within the building. It is so large that the visual effect is to create a link between the enormous dome which appears to float above it, and the congregation at floor level of the basilica. It is penetrated visually from every direction, and is visually linked to the Cathedra Petri in the apse behind it and to the four piers containing large statues that are at each diagonal.

St. Peter's Piazza

To the east of the basilica is the Piazza di San Pietro, (St. Peter's Square). The present arrangement, constructed between 1656 and 1667, is the Baroque inspiration of Bernini who inherited a location already occupied by an Egyptian obelisk which was centrally placed, (with some contrivance) to Maderno's facade. The obelisk, known as "The Witness", at 25.31 metres (83.0 ft) and a total height, including base and the cross on top, of 40 metres (130 ft), is the second largest standing obelisk, and the only one to remain standing since its removal from Egypt and re-erection at the Circus of Nero in 37 AD, where it is thought to have stood witness to the crucifixion of Saint Peter. Its removal to its present location by order of Pope Sixtus V and engineered by Domenico Fontana on 28 September 1586, was an operation fraught with difficulties and nearly ended in disaster when the ropes holding the obelisk began to smoke from the friction. Fortunately this problem was noticed by Benedetto Bresca, a sailor of Sanremo, and for his swift intervention, his town was granted the privilege of providing the palms that are used at the basilica each Palm Sunday.

The other object in the old square with which Bernini had to contend was a large fountain designed by Maderno in 1613 and set to one side of the obelisk, making a line parallel with the facade. Bernini's plan uses this horizontal axis as a major feature of his unique, spatially dynamic and highly symbolic design. The most obvious solutions were either a rectangular piazza of vast proportions so that the obelisk stood centrally and the fountain (and a matching companion) could be included, or a trapezoid piazza which fanned out from the facade of the basilica like that in front of the Palazzo Pubblico in Siena. The problems of the square plan are that the necessary width to include the fountain would entail the demolition of numerous buildings, including some of the Vatican, and would minimize the effect of the facade. The trapezoid plan, on the other hand, would maximize the apparent width of the facade, which was already perceived as a fault of the design.

Bernini's ingenious solution was to create a piazza in two sections. That part which is nearest the basilica is trapezoid, but rather than fanning out from the facade, it narrows. This gives the effect of countering the visual perspective. It means that from the second part of the piazza, the building looks nearer than it is, the breadth of the facade is minimized and its height appears greater in proportion to its width. The second section of the piazza is a huge elliptical circus which gently slopes downwards to the obelisk at its centre. The two distinct areas are framed by a colonnade formed by doubled pairs of columns supporting an entablature of the simple Tuscan Order.

Clocks

The top of the facade of St. Peter's Basilica has two clocks and several sculptures. The clocks were created to replace Bernini's bell towers which had to be torn down due to insufficient support. The left hand clock shows Rome time, the right hand one shows European mean time. The statues are Christ the Redeemer, St. John the Baptist and 11 Apostles. From the left: St. Thadeus, St. Matthew, St. Philip, St. Thomas, St. James the Greater, St. John the Baptist, The Redeemer, St. Andrew, St. John the Evangelist, St. James the Lesser, St. Bartholomew, St. Simeon, and St. Matthias. Above the Roman clock is the coat of arms for the city-state of Vatican City since 1931 held by two angels.

Bells

The Basilica has 6 bells, placed in the room under the Roman clock, only 3 of them are visible from ground level while the rest are hidden behind the bourdon. They range from the smallest which is 235 kg to the massive bourdon that approximately weighs 9 tonnes. From 1931, the bells are operated electrically, thus permitting even the largest bell to be tolled from a distance. The oldest bell Rota dates from 1353, and the bourdon called Campanone is rung at Christmas and Easter, on the Solemnity of Sts. Peter and Paul, and every time the Pope imparts the "Urbi et Orbi" blessing to the city and to the world. Campanone also announces the death of the pope and an election of a new pope.

Treasures

Tombs and relics

There are over 100 tombs within St. Peter's Basilica (extant to various extents), many located beneath the Basilica. These include 91 popes, Saint Ignatius of Antioch, Holy Roman Emperor Otto II, and the composer Giovanni Pierluigi da Palestrina. Also buried here are Queen Christina of Sweden, who abdicated her throne in order to convert to Catholicism, and Countess Matilda of Tuscany, supporter of the Papacy during the Investiture Controversy, as well as British royal Jacobites of the exiled House of Stuart granted asylum by Pope Clement XI, namely James Francis Edward, his wife Maria Clementina Sobieska, and their sons, Charles Edward and Henry Benedict, Cardinal-Bishop of Frascati. The most recent interment was Pope Benedict XVI, on 5 January 2023. Beneath, near the crypt, is the recently discovered vaulted fourth-century "Tomb of the Julii". (See below for some descriptions of tombs).

Artworks

In the towers to either side of the facade are two clocks. The clock on the left has been operated electrically since 1931. Its oldest bell dates from 1288.

One of the most important treasures of the basilica is a mosaic set above the central external door. Called the "Navicella", it is based on a design by Giotto (early 14th century) and represents a ship symbolizing the Christian Church. The mosaic is mostly a 17th-century copy of Giotto's original.

At each end of the narthex is an equestrian figure, to the north Constantine the Great by Bernini (1670) and to the south Charlemagne by Cornacchini (18th century).

Of the five portals from the narthex to the interior, three contain notable doors. The central portal has the Renaissance bronze door by Antonio Averulino (called Filarete) (1455), enlarged to fit the new space. The southern door, the Door of the Dead, was designed by 20th-century sculptor Giacomo Manzù and includes a portrait of Pope John XXIII kneeling before the crucified figure of Saint Peter.

The northernmost door is the "Holy Door" which, by tradition, is walled-up with bricks, and opened only for holy years such as the Jubilee year by the Pope. The present door is bronze and was designed by Vico Consorti in 1950 and cast in Florence by the Ferdinando Marinelli Artistic Foundry. Above it are inscriptions commemorating the opening of the door: PAVLVS V PONT MAX ANNO XIII and GREGORIVS XIII PONT MAX.

Recently installed commemorative plaques read above the door as follows:

PAVLVS VI PONT MAX HVIVS PATRIARCALIS VATICANAE BASILICAE PORTAM SANCTAM APERVIT ET CLAVSIT ANNO IVBILAEI MCMLXXV(Paul VI, Pontifex Maximus, opened and closed the holy door of this patriarchal Vatican basilica in the jubilee year of 1975.)

IOANNES PAVLVS II P.M. PORTAM SANCTAM ANNO IVBILAEI MCMLXXVI A PAVLO PP VI RESERVATAM ET CLAVSAM APERVIT ET CLAVSIT ANNO IVB HVMANE REDEMP MCMLXXXIII–MCMLXXXIV(John Paul II, Pontifex Maximus, opened and closed again the holy door closed and set apart by Pope Paul VI in 1976 in the jubilee year of human redemption 1983–1984.)

Archpriests since 1053

List of archpriests of the Vatican Basilica: