St. Peter's Basilica, is a Late Renaissance church located within the Vatican City. St. Peter's Basilica has the largest interior of any Christian church in the world. It is regarded as one of the holiest Catholic sites. It has been described as "holding a unique position in the Christian world" and as "the greatest of all churches of Christendom".

In Catholic tradition, the basilica is the burial site of its namesake Saint Peter, who was one of the twelve apostles of Jesus and, according to tradition, first Bishop of Rome and therefore first in the line of the papal succession. Tradition and some historical evidence hold that Saint Peter's tomb is directly below the altar of the basilica. For this reason, many Popes have been interred at St Peter's since the Early Christian period. There has been a church on this site since the 4th century. Construction of the present basilica, over the old Constantinian basilica, began on April 18, 1506 and was completed on November 18, 1626.

St. Peter's is famous as a place of pilgrimage, for its liturgical functions and for its historical associations. It is associated with the papacy, with the Counter-reformation and with numerous artists, most significantly Michelangelo. As a work of architecture, it is regarded as the greatest building of its age. Contrary to popular misconception, Saint Peter's is not a cathedral, as it is not the seat of a bishop. It is properly termed a papal basilica. The Basilica of St. John Lateran is the cathedral church of Rome.


The Basilica of St. Peter is a huge church in the Renaissance style located in Rome 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 Piazza, a forecourt in two sections, both surrounded by tall colonnades. The first space is oval and the second trapezoid. The facade 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 metres (18.2 ft) statues of the 1st century apostles to Rome, Saint Peter and Saint 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. 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, only opened in Holy Years.

The interior is of vast dimensions by comparison with 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."

There is a barrel-vaulted nave, the highest of any church, leading to the central dome. The aisles are lower and have a number of chapels off them. There are also chapels surrounding the central 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 Clementine Chapel with the altar of St Gregory, the Sacristy Entrance, the left transept with altars to the Crucifixion of St Peter, St Joseph and St Thomas, the altar of the Sacred Heart, the Chapel of the Madonna of Colonna, the altar of St Peter and the Paralytic, the apse with St Peter's Cathedra, the altar of St Peter raising Tabitha, the altar of the Archangel Michael, the altar of the Navicella, the right transept with altars of St Erasmus, Saints Processo and Martiniano, and St Wenceslas, the altar of St Basil, the Gregorian Chapel with the altar of the Madonna of Succour, the larger Chapel of the Holy Sacrament, the Chapel of St Sebastian and the Chapel of the Pieta.

The entire interior is lavishly decorated with marble, reliefs, architectural sculpture and gilding. The basilica contains a large number of tombs of popes and other notable people, many of which are considered outstanding artworks. There are also a number of sculptures in niches and chapels, including Michelangelo's Pieta. The central feature is a baldachin, or canopy over the Papal Altar, designed by Gianlorenzo Bernini. The sanctuary culminates in a sculptural ensemble, also by Bernini, and containing the symbolic Chair of St Peter.

One observer wrote: "St Peter's Basilica is the reason why Rome is still the center of the civilized world. For religious, historical, and architectural reasons it by itself justifies a journey to Rome, and its interior offers a palimpsest of artistic styles at their best..."

The American philosopher Ralph Waldo Emerson described St Peter's as "an ornament of the earth ....the sublime of the beautiful."