To celebrate the Barberini family’s rise to papal force, this sumptuous baroque palace appeal even before you see its stunning craftsmanship assortment. Some prominent architects chipped away at it, including rivals Bernini and Borromini; the previous contributed a square staircase, the last a helicoidal one. In the midst of the masterpieces on display, don't miss Filippo Lippi's Annunciazione and Pietro da Cortona's roof fresco Il Trionfo della Divina Provvidenza . Other must-sees incorporate Hans Holbein's famous picture of a pugnacious Henry VIII (c 1540) and Raphael's La Fornarina, thought to be a representation of his mistress, who worked in a pastry kitchen in Trastevere.