Designed by some of Italy's most infamous master artists, St. Peter's Basilica is not only the world's largest church but is also one of its most spectacular. Originally built at the site of St. Peter's grave around 349 CE by Emperor Constantine, the basilica, as it stands today, was consecrated in 1626 at the culmination of over 120 years of construction. The original designs were laid out by Bramante in 1506, however, over the following years, the ambitious designs were altered by several renown architects including Michelangelo, Giacomo Della Porta and Carlo Maderno, each adding their own personal touch to the magnanimous design. St. Peter's Basilica now enshrines some of the world's most famed artworks including Michelangelo's Pieta and Bernini's Baldachin. The splendid facade and riches that lie within are crowned by an intricately adorned dome that is revered as Michelangelo's most grand architectural legacy. The Pope delivers the Urbi et Orbi blessing each year on the occasion of Christmas and Easter from the basilica's central balcony, attracting millions of devout pilgrims to the threshold of St. Peter's each year. He remains the only one who can serve at the high altar of St. Peter's Basilica.