Chenal du Four, Brittany, France (with Map & Photos)

The Chenal du Four is a pass of the Iroise located between Pointe Saint-Mathieu and the Island of Béniguet. Marked by the lighthouses of Saint-Mathieu and Kermorvan, navigation is regulated by an order of the maritime prefecture of the Atlantic. The northern and southern limits of the channel are respectively the Four lighthouse and the Vieux Moines turret near Pointe Saint-Mathieu.

Chenal du Four
Chenal du Four

At the tip of Brittany, the Chenal du Four, which bears the name of its emblematic lighthouse, is one of the passages giving access to or leaving the Iroise Sea. Here, the strong tidal currents can raise rough seas if the swell is there. To borrow this channel, it will be necessary to take some precautions which we will deliver to you.

Chenal du Four
Chenal du Four

Le Four, a singular passage


The Chenal du Four is nothing like the raz Blanchard, the Fromveur or the raz de sein. Let's see its features:

  • The Chenal du Four is a coastal passage, but apart from the Aber Ildut, there is no shelter on the way allowing a stopover. The port of Le Conquet dries up at low tide.
  • The Chenal du Four is a fairly long passage between the eponymous lighthouse and Pointe Saint Mathieu. We will count almost 13 minutes, while the breast flush is much shorter (2 to 3 minutes). In other words, if you will go very fast with the favorable current, this trip will last an eternity against the current.
  • The reduced width of this channel does not invite you to tack or you won't have to count your tacks or gybes.
  • The outer edges of the channel are literally poorly paved, covered in emergent rocks. You should only leave the channel with good control of your position on the chart.
  • And as in all passages involving a strong current, let's not forget that the wind opposing the current will raise rough seas, but this time in the Four Channel there is some distance to cover.

Chenal du Four
Chenal du Four

The Lighthouse of the Chenal du Four is a monument in the municipality of Porspoder (Finistère, Brittany). It is an attraction for holidaymakers staying in the region.

Chenal du Four Map