The museums, housed primarily in the former papal apartments of the medieval Apostolic Palace, cover the Renaissance from its late 14^th-century origins to its full flower in the 16^th century. Among the artists whose works visitors can find there are Botticelli, Fra Angelico, Signorelli, Michelangelo and Raphael. Of course the capstone of the Renaissance collection is the Sistine Chapel.

But even the Vatican’s museums play second fiddle to the great edifice that dominates Vatican City: the magnificent basilica of St. Peter’s, the largest church in Christendom, and beneficiary of some of Michelangelo and Bernini’s greatest works. Bernini’s great twin colonnades of robust, piazza-forming, Tuscan-order pillars, which seem to stretch in an immense embrace from the basilica, were for years the ceremonial entrance to the Vatican for diplomatic travelers. They would ride their carriages or horses along the wide, curving path formed under the colonnade roof, catching tantalizing glimpses between the great pillars of St. Peter’s facade.

Bernini had planned at one time to construct a third colonnade at the bottom of the piazza, hoping to block off the view of the great church from casual passersby while rewarding determined pilgrims who would work their way through the columns with a first, breathtaking view of the basilica.

His other great contribution was the soaring, 95-foot tall bronze baldachino, with its renowned twisted spiraling columns, over the main altar of St. Peter’s. Bernini’s baldachino, essentially a canopy traditionally placed over a sacred spot, has always been to central focal point of the basilica.

That is until the eye gazes upward at Michelangelo’s magnificent dome, the best known and most imitated in the world. He designed the dome, which is even larger than Brunelleschi’s prodigious Il Duomo in Florence, to rest on four massive piers that form the transept of St. Peter’s. But he made certain that the cornices of the piers would have such a powerful horizontality that they would make the dome itself appear to float above them. Visitors over a span of almost 400 years have come away wondering how such a large dome seems to rest so lightly on its foundation. — Patrick Totty