St. Peter's Basilica was built on the site of the 4th century Roman temple and has been renovated several times, compatible with different architectural styles. St. Peter's Basilica is so important because Calvin, the founder of Protestant thought, promoted his religious ideas here and in the Calvin lecture hall next to it, which is a landmark of the Reformation. You can also climb the tower north of the church, with a sweeping view of Lake Lemon and the city of Geneva.