Saint Saturnin early evangelized the inhabitants of the city of Lugdunum Convenarum (former name of Saint-Bertrand). At that time, we probably already found a small oratory... Anyway, bishop Bertrand de L'Isle rebuilt a cathedral and a cloister in 1082.
Bertrand let his name to the small city and he was buried in his cathedral. A huge crowd of pilgrims immediately came to see his grave. So, the future pope Clement V, also known as Bertrand de Got, decided to extend the cathedral in 1350.
Inside, don't miss saint Bertrand's mausoleum, given by cardinal of Foix and bishop of Comminges, Pierre, in 1432, and also the nice Renaissance stalls!