Loch Earn, Perthshire. In the west of Strathearn lies the stretch of water known as Loch Earn. The deepest part (87m) is located near the western end. It is 10.5 km from east to west and at it's widest is 0.8 km. Lochearnhead is situated at its western end of the Loch and St. Fillans village at the eastern. From here the River Earn flows east out of the Loch, down through Strathearn and joins the River Tay Estuary 75 km away. The Loch basin was dug out by the enormous erosional power of ice during the glacial periods of the last 2million years.
