The belfry straddles the main gate of the fortified village. There were five gates altogether (see map). Called either Lachard Gate (Porte du Lachard) or Large Gate (Grande Porte), it was carefully maintained and guarded through the centuries for fear of attackers, prowlers and lepers, but also of wild beasts – wolves, lynxes and boars – coming from the nearby forest.
     After the death of the last of the Poitiers de Valentinois, the seigneury was taken over by the heir to the throne of France, the Dauphin, future King Louis XI, and the ceremony took place on 29 March 1426 in the little room inside the door below the belfry. The city keys were handed over and freedoms, franchises and customs were confirmed.
    Often attacked and destroyed until the 17th century, the old watch-tower had to be repaired several times, the last buttresses being built against its walls in Year X of the Revolution (1801-1802) and in 1849.
    Also called the Clock Tower (Tour de l'Horloge) after a clock was installed in 1726, it is mainly known as the belfry (beffroi) nowadays. Two bells, blessed in 1724 and 1732 respectively, marked the passage of time and local events until 1970, using a code of chimes known by all locally. As civil property of the Community, they were the only bells in Marsanne not sent to a foundry during the Revolution to become cannons.