The Leff ( br, Leñv) is a river in

Brittany Brittany (; french: link=no, Bretagne ; br, Breizh, or ; Gallo: ''Bertaèyn'' ) is a peninsula, historical country and cultural area in the west of modern France, covering the western part of what was known as Armorica during the period ...

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan area ...

. It is long. It flows into the Trieux near

Pontrieux Pontrieux (; ) is a town and commune in the Côtes-d'Armor department of Brittany in northwestern France. Population Inhabitants of Pontrieux are called ''pontriviens'' in French. See also *Communes of the Côtes-d'Armor department The fo ...

Places in or near Leff

In the valley of Leff, there is a town called

Châtelaudren Châtelaudren (; br, Kastellaodren; Gallo: ''Le Chastèu'') is a former commune in the Côtes-d'Armor department of Brittany in northwestern France. On 1 January 2019, it was merged into the new commune Châtelaudren-Plouagat.Rivers of France Rivers of Brittany Rivers of Côtes-d'Armor 1Leff {{France-river-stub