The Fier is a 72.2 km (44.9 mi) long river in the Haute-Savoie and Savoie départements, southeastern France.
Its source is at Manigod, in the Aravis Range. It flows generally west.
It is a left tributary of the Rhône into which it flows at Seyssel.
Among its tributaries are the Chéran and the Thiou, that drains Lake Annecy.
The Gorges du Fier is a spectacular natural gorge located near the town of Lovagny, about 10 kilometers west of Annecy in the Haute-Savoie region of France, formed by the Fier River, which has carved its way through the rocks over millennia, creating deep, narrow canyons.
