The Tourelle de la Plate, also known as Petite Vieille (Little Old Woman) is a lighthouse

Lighthouse

A lighthouse is a tower, building, or other type of structure designed to emit light from a system of lamps and lenses or, in older times, from a fire, and used as an aid to navigation for maritime pilots at sea or on inland waterways....

 in the dangerous strait Raz de Sein

Raz de Sein

The Raz de Sein is a stretch of water located between the Isle of Sein and the Pointe du Raz in Finistère in the Brittany region of France.This tidal water is an essential passage for vessels wishing to pass between the Atlantic and the English Channel, because further west at high tide the Isle of...

, off the northwest coast of France, belonging to the departement of Finistère

Finistère

Finistère is a département of France, in the extreme west of Brittany.-History:The name Finistère derives from the Latin Finis Terræ, meaning end of the earth, and may be compared with Land's End on the opposite side of the English Channel...

 in the region

Régions of France

France is divided into 27 administrative regions , 22 of which are in Metropolitan France, and five of which are overseas. Corsica is a territorial collectivity , but is considered a region in mainstream usage, and is even shown as such on the INSEE website...

 of Brittany. It is a companion to La Vieille

La Vieille

La Vieille is a lighthouse in the département of Finistère at the commune of Plogoff, on the northwest coast of France. It lies on the rock known as Gorlebella , guiding mariners in the strait Raz de Sein, across from the companion lighthouse Tourelle de la Plate—also known as Petite Vieille...

.

At a meeting on 5 June 1886, the lighthouse commission decided to construct a new tower near the La Vieille lighthouse, which was itself then in progress.