Tibidy is a French islet at the mouth of the river Faou

Le Faou

Le Faou is a commune in the Finistère department in Bretagne in northwestern France.-Population:Inhabitants of Le Faou are called Faouistes.-Events:...

, at the bottom of the roadstead of Brest

Roadstead of Brest

The roadstead of Brest is a roadstead or bay located in the Finistère department in Brittany in northwestern France. The surface area is about 180 km² . The port of Brest is located on its northern edge and one of the two French naval bases...

, on land belonging to the commune of L'Hôpital-Camfrout

Hôpital-Camfrout

Hôpital-Camfrout is a commune in the Finistère department of Brittany in north-western France.-Population:Inhabitants of Hôpital-Camfrout are called in French Hospitaliers or Camfroutois.-References:** ;-External links:* *...

. Its highest point is 15m. The island houses a private manor and is linked to the mainland by a spit

Spit (landform)

A spit or sandspit is a deposition landform found off coasts. At one end, spits connect to land, and extend into the sea. A spit is a type of bar or beach that develops where a re-entrant occurs, such as at cove's headlands, by the process of longshore drift...

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A legend given in the life of Saint Guénolé by the cartulary of Landévennec Abbey

Landévennec Abbey

Landévennec Abbey was a monastery in Brittany, now in Finistère, France. It existed from its foundation at Landévennec, traditionally by Winwaloe in the late fifth century, to 1793, when the monastery was abandoned and sold. In 1950 it was bought and rebuilt by the Benedictines of Kerbénéat.It...

 states that Saint Guénolé, accompanied by 11 other disciples of Saint Budoc

Budoc

Saint Budoc of Dol was a Bishop of Dol, venerated after his death as a saint in both Brittany and Devon . Saint Budoc is the patron of Plourin Ploudalmezeau in Finistère where his relics are preserved...

, arrived from Île Lavret (archipelago of Bréhat) on île de Tibidy and there set up an oratory. Three years later, they left the island and reached Landévennec

Landévennec

Landévennec is a commune in the Finistère department of Brittany in north-western France.-Ship graveyard:Shortly before entering the roadstead of Brest, the river Aulne forms a bend around the Île de Térénez then the pointe de Pen Forn near Landévennec, where there is 10m depth of water regardless...

, with the island then being given to Landévennec Abbey by Gradlon

Gradlon

Gradlon the Great was a semi-legendary 5th century "king" of Cornouaille who became the hero of many Breton folk stories. The most famous of these legends is the story of the sunken city of Ys. He is supposed to have been the son of Conan Meriadoc.-Gradlon and Malgven :According to some legends,...

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