The province of Brittany, in North-western part of France, forms a large peninsula that stretches towards the Atlantic Ocean bordered by the English Channel to the north and the Bay of Biscay to the south. The waters located between the western coast and Ushant island form the Iroise Sea. This section of the coastline of Brittany remains one of the most dangerous seas in Europe with frequent violent storms, huge waves and strong currents. Over thirty ships were lost in this region between 1888 and 1904. Because of this, the rugged coastline is crowded with lighthouses - more than one third of all the lighthouses and fire towers illuminating the French coast are located here. These granite fortresses have been warning distant sailors of the dangers of this jagged coastline and treacherous rocks since the 18th century.

One of the most famous lighthouse is the one built on a rock called La Jument, about 300 metres from the coast of the island of Ushant. La Jument became well known in 1989, through a series of photographs taken by Jean Guichard.