The Ar-Men lighthouse (“the rock” or “the stone” in Breton) is a sea lighthouse built between 1867 and 1881 at the end of the Chaussée de Sein, on Western Brittany Coast, in France.

This particularly lighthouse was built in order to protect ships from a very large reef extended over 13 miles (24 km) to west of the Ile de Sein, and it is extremely dangerous to cross that area.
There was no monotony in the life of the lighthouse keepers managing Ar Men: storms observed directly in the midst of them for several days up at thirty meters about above the water level with the only music of the wind strength. All of this by living without to consider that a very huge wave could been able to tear apart the whole structure.
After the storm the repair job was a regular work to apply on awash kitchen, doors, windows, and integrity of the walls.

At 1921 a guardian was overwhelmed by an anomalous wave while observing a ship in the storm. Since then a parapet was positioned around the platform and the dock. Nevertheless, other guards did the same end in the course of the 20th Century.

In December 1923 a fire broke out in the platform but was later extinguished.

During the Second World War, Ar-Men’s guards had to permanently accommodate three German Soldiers on the lighthouse. Germans gave peremptory order that Ar-Men had to light only on the passage of German Navy ships, opportunely highlighted by Navy personnel via radio. In October 1941, one of the guards, Francois Violant, saved a German soldier who fell into the water in order to catch a cormorant killed with his rifle.