César Tower, Medieval tower in Provins, France

César Tower is a 12th-century keep in Provins, built on a square base that becomes octagonal at mid-height, with four corner turrets. A wooden gallery encircles the tower below its pyramidal roof, and a lower stone building adjoins it. Inside are a vaulted ground-floor hall, a higher guard room, and dungeons reached by narrow passages.

A tower existed here by 1137, named in the charter fixing the Champagne fairs' limits. The present keep was probably built after 1150 under Henry the Liberal, Count of Champagne, and was planned as a prison from the start. The English occupied it during the Hundred Years' War and added a masonry wall after the 1432 siege. It was listed as a monument historique in 1846.

The name César stems from a legend that Julius Caesar built the tower, though no source places Caesar in Provins; the name instead signals power, as the similarly built Temple tower was also called Tour César. The tower serves as a belfry: its great bell, cast in 1511 and taken from the collapsed Saint-Quiriace bell tower in 1689, weighs 3,000 kg and bears a verse naming it Quiriace.

Reaching the upper levels involves climbing several steep spiral staircases, so comfortable walking shoes are recommended for the visit. The interior spaces are generally accessible to visitors, though the ascent requires a reasonable level of physical fitness.

The tower's bells tell a story of survival: of six original bells, five were melted down in 1793 and 1798 to make cannons and coins. The largest remaining bell, cast in 1511, measures 1.48 m across and weighs 3,000 kg; its inscription names it after Saint Quiriace and claims it drives away devil, thunder and hail.