The document discusses Renaissance architecture between 1400-1600 AD. Renaissance architecture was inspired by classical Greek and Roman architecture, with an emphasis on symmetry, proportion, and geometry. There were three periods - Early Renaissance from 1400-1500 focused on adopting classical details; High Renaissance from 1500-1525 showed mastery of the style in different building types; and Mannerism from 1520-1600 experimented with spatial relationships. St. Peter's Basilica is highlighted as one of the greatest buildings of the Renaissance, constructed over multiple decades and designs by architects like Bramante and Michelangelo.