The Apostle's tomb
The history of St Peter's Basilica begins with a tomb. According to Christian tradition, the apostle Peter was martyred in Rome under Nero, probably between 64 and 68 AD, in the Neronian circus that stood on the Vatican hill. Roman Christians buried him at the edge of the circus, along the Via Cornelia. That tomb soon became a place of pilgrimage.
Archaeological research conducted beneath the basilica between 1939 and 1950 identified bone remains in a niche below the high altar, marked with graffiti invoking Peter's name. In 2013 Pope Francis publicly displayed some of those bones, reconsecrated in a rite. Their attribution to the first apostle remains a subject of scholarly debate, but the site's association with Peter is documented as early as the second century.
The Constantinian basilica (320–330 AD)
Emperor Constantine I, following the Edict of Milan (313 AD), ordered the construction of a great basilica on the site of Peter's tomb. Work began around 320 AD and was completed around 330. The Constantinian structure was imposing by fourth-century standards: five naves, a length of approximately 100 m, a capacity of several thousand worshippers.
This first basilica stood for over eleven centuries — from its inauguration until its gradual demolition, begun in 1506 by Pope Julius II. It was the oldest and most venerated church in Western Christendom.
The medieval crisis and the Renaissance project
During the Middle Ages the Constantinian basilica deteriorated badly. In 1452 Pope Nicholas V commissioned Leon Battista Alberti and Bernardo Rossellino to design an extension. Work halted at Nicholas V's death.
The radical project came with Julius II in 1505–1506: tear down the old basilica entirely and build a new one of unprecedented scale. The commission went to Donato Bramante, who conceived a Greek-cross plan with a central dome inspired by the Pantheon. The foundation stone was laid on 18 April 1506.
The construction of the century (1506–1626)
The building took 120 years and involved the greatest architects of the Renaissance and Baroque:
- Donato Bramante (1506–1514): original Greek-cross design
- Raphael (1514–1520): revision towards a Latin cross
- Antonio da Sangallo the Younger (1520–1546): further modifications
- Michelangelo Buonarroti (1546–1564): return to the Greek cross, definitive design of the dome — his greatest architectural legacy
- Giacomo della Porta (1564–1590): completion of the dome, partly modified from Michelangelo's design
- Carlo Maderno (1607–1614): addition of the longitudinal nave in Latin-cross plan and the current façade
- Gian Lorenzo Bernini (1629–1680): the bronze baldachin over the high altar, the nave decoration, and above all the colonnade of St Peter's Square
The official consecration took place on 18 November 1626 — exactly 1,300 years after the first Constantinian consecration.
The dimensions: the world's largest church
St Peter's Basilica is the largest church in the Christian world by internal volume:
- Internal length: 186 m
- Nave width: 58 m
- Nave height: 46 m
- Dome height (interior): 119 m from floor to lantern
- External height of the cross at the dome's summit: 136 m
- Floor area: approximately 15,000 m²
- Capacity: approximately 60,000 people
Bernini's colonnade: the great embrace
Between 1656 and 1667 Bernini created the elliptical colonnade embracing St Peter's Square: 284 columns and 88 pillars in travertine, arranged in four rows, surmounted by 140 statues of saints. Bernini described the colonnade as "the open arms of the Catholic Church embracing the faithful".
The two foci of the ellipse — marked by two circular slabs in the square's pavement — are the points from which all four rows of columns appear perfectly aligned, creating a single row.
The basilica as a geopolitical symbol
For centuries St Peter's Basilica was not just a place of worship but the symbolic centre of world Catholicism. Here popes were crowned (until 1964), saints beatified, and Conclaves held (until the 15th century). Here Napoleon was crowned in 1804 — not in Rome, but he was profoundly affected by his visit.
Today the basilica is technically a church of the Vatican State, not Rome's cathedral (Rome's cathedral is St John Lateran). The pope celebrates the most solemn masses of the liturgical year here.
Visit with a private driver
Reach St Peter's Basilica with a private driver. From Termini station, your hotel or the airport — your driver takes you directly to the Vatican. Service from €49. → Book at myromedriver.com
Frequently Asked Questions
Is St Peter's the largest church in the world? Yes, by internal volume. The Basilica of Yamoussoukro in Ivory Coast has a larger floor area, but St Peter's internal volume remains unsurpassed.
When was the dome built? The design is by Michelangelo (1546–1564); construction was completed by Giacomo della Porta in 1590, with some modifications to the original shape.
Who is buried in the basilica? Besides Peter, dozens of popes are buried in the Vatican crypt (Vatican Grottoes), including John Paul II and John XXIII.
Article no. 121 — TIER S — MON-07 San Pietro Type: HISTORICAL Words: ~1,000