In the small Vatican state, lying in the urban area of Rome , stands St. Peter's Basilica, its huge bulk dominating the place of the same name, stretching in front of it. The latter is framed by a fascinating colonnade, the superb Baroque creation of Bernini, welcoming into its embrace the millions of worshippers and tourists arriving from every corner of the world to admire the beauty of the most authoritative and grandiose church in Christendom. Giuliano da Sangallo and Donato Bramante designed the basilica - built on the site of the ancient church built for the Emperor Constantine on the tomb of the apostle Peter - and work began in 1506 for Pope Julius II. These two artists were followed in 1514 by Raphael and in 1546 Michelangelo who, returning to Bramante's Greek cross plan, enhanced the harmonious, slender lines of the building with a splendid, grandiose dome, which was finished at the end of the sixteenth century by Giacomo della Porta. In the early years of the seventeenth century, Paul V charged Carlo Maderno with the task of transforming the configuration, for liturgical reasons, from a Greek to a Latin Cross, and to create the sumptuous façade of the basilica which - preceded by three ramps of steps, the fine work of Bernini, flanked by the imposing statues of St. Peter and St. Paul - is spanned by Corinthian columns and pilasters, and has nine balconies, including the central loggia of the Benedictions, where the election of the new Pontiff is announced. In a central position the figure of Christ dominates from a high balustrade, flanked by the statues of the apostles and St. John the Baptist. Symbol of the universality of the Church, the monumental basilica was consecrated in November 1626, under the pontificate of Urban VIII. Entry is gained through five magnificent bronze portals, including the Holy Door, opened by the pope only in Jubilee years. The solemn interior with its three naves contains numerous sumptuous chapels housing an immense artistic heritage: among the many masterpieces there are the works of Bernini, such as the famous bronze, wooden and marble canopy, placed over the main altar, the massive tomb of Urban VIII, the attractive St. Peter's chair, supported by the colossal statues of the Church fathers and adorned by a series of splendid sculptures of swirling angels, the celebrated Pietà sculpted by Michelangelo between 1497 and 1499 for the French cardinal Jean Bilhères de Lagraulas, his only signed work, the bronze statue of St. Peter, the admirable work of Arnolfo di Cambio, the sepulchral monuments of Clement XIII, the superb eighteenth-century work of Antonio Canova, Paul III, by Guglielmo della Porta, and the tomb of Innocent VIII, by Pollaiolo in 1498.