The Cathédral St-Pierre was begun in the 12th Century and is a mixture of Romanesque and Gothic styles. In the 18th Century a classical facade was added, which looks rather out of place. Unfortunately, it is very difficult to get far enough away from the building to take a decent photograph!
The cathedral is the highest point of the old town, and the tower offers stunning views of the harbour in one direction, and Mont Salève in the other. In the summer, there are also organ and carillon recitals at the weekend.