Loch Ossian is a narrow loch that is about 5 kilometres (3.1 mi) long on the north eastern edge of Rannoch Moor, on The Corrour Estate, with its western corner 2 kilometres (1.2 mi) east of Corrour railway station. It is drained by the River Ossian, flowing north into Loch Guilbinn and ultimately to the River Spean at Moy.