The atrium (corresponding to the ancient portico of the early Christian basilicas) is considered one of the most remarkable works of Carlo Maderno and was built between 1608 and 1612. The central door is by the Florentine sculptor Antonio Averulino, known as Filarete. It dates from 1455 and comes from the ancient Constantinian church. Saint Peter and Saint Paul are represented here with scenes from their martyrdoms. The Holy Door stands on the right, cast in bronze by the sculptor Vico Consorti in 1950. This door is opened and closed in the Pope’s presence during every Jubilee Year. On the far left of the vestibule is the equestrian statue of Charlemagne, crafted by Agostino Cornacchini (1725). On the right vestibule stands Bernini’s equestrian statue of the Emperor Constantine (1670). The Latin cross structure of the interior dates back to the early 1600’s and was designed by Maderno, who completed the basilica and built the nave and the two aisles, forming a whole with the Michelangelesque central octagon. It is an immense and magnificent space, richly decorated with Baroque stuccos, mosaics and statues, almost overwhelming at first glance.
The visitor usually needs to pause for a moment before he can take in its vast size. Simply comparing the height of the holy-water fonts and their supporting puttos with that of the people around them can give an idea of the church’s proportions. The basilica is 187 metres long, 58 metres wide across the aisles and 140 metres wide at the transept: the maximum height of the vault in the nave is 46 metres (as high as a 15 storey building!).
The visitor should first walk down the nave, noting the marks on the floor indicating the comparative lengths of the largest churches in the world. He can then retrace his steps to the aisle near the entrance door. The nave has huge, fluted and cabled pilasters (the lower part of the fluting is full). Each one has niches with 39 statues of saints who were founders of various religious orders and congregations. The vault was decorated with gold stuccos in 1780, under Pius VI.
The right aisle, facing the altar, contains many great artistic and religious works. Michelangelo’s Pietà is in the first chapel, shielded by thick glass. This masterpiece dates from 1499, when the artist was only 24 years old.
The Madonna’s youthful, sweet face expresses her submission to destiny, as she cradles the dead Christ’s limp body in her lap. Yet the rich drapery of her dress and veil suggest an extraordinary physical and moral strength, which contrasts with the delicate, 15th century features. This is the only work signed by the artist, whose name appears on the belt. The Chapel of the Most Holy Sacrament follows next, with a tabernacle on the altar resembling Bramante’s Tempietto at Saint Peter’s in Montorio, on the Janiculum Hill. Bernini fashioned this gilded bronze tabernacle in 1674. Two kneeling angels were added to it later on.
At the end of the right aisle is the famous monument to Gregory XIII (1572-1585), completed by the sculptor Camillo Rusconi in 1723, with allegorical figures of Religion and Fortitude and a dragon, the heraldic symbol of the Pope’s family, below the sarcophagus.
Returning to the nave, one can see the famous statue of Saint Peter Enthroned, which most critics have attributed to Arnolfo di Cambio (1245-1302). Some scholars, however, date the statue to the 5th century. One foot has been almost completely worn away by the faithful, who kiss it to show their devotion to the saint. Four huge, square pilasters mark where the longitudinal nave and transept meet. Niches have been carved out of the pilasters’ oblique walls, containing four colossal statues which embody crucial moments of Christ’s passion: St Longinus, the soldier who pierced Christ’s side with his spear and later converted to Christianity; St Helen, Emperor Constantine’s mother, who brought the cross and nails of Christ’s martyrdom to Rome; St Veronica, who wiped Christ’s face with a cloth on the road to Calvary; St Andrew, Peter’s brother, who was crucified in Greece. The first of these statues was executed by Bernini in 1638; the latter three statues were sculpted by his pupils. The papal altar in the middle of the church is surmounted by the famous gilded bronze baldachin, designed by a youthful Bernini between 1624 and 1632. It stands 29 metres high and was commissioned by Pope Urban VIII Barberini (1623-1644) to fill the “empty” space below the dome and create an upward movement.