Loch Earn is a freshwater loch in the Highlands, within Perthshire. It is the source of the River Earn which flows south to the feetile plains of Strathearn. The name of the loch in Gaelic is Loch Eire or Loch Éireann and is thought to mean "Loch of Ireland"; and it has been suggested that this might derive from the time when the Gaels were expanding their kingdom of Dál Riata eastwards into Pictland, though this may be mere romantic imagining.
Loch Earn is a long narrow loch, 10 miles west of Crieff and is approximately 6½ miles long, ¾ mile at its widest point (56.38N, 4.22W) and at its deepest point (approximately halfway along) about 285 feet. Lochearnhead village is situated at the western end of the loch and St. Fillans village at the eastern end. From here, the River Earn flows eastwards from the loch, through Strathearn, and eventually joins the Firth of Tay some 50 miles away. Lochearnhead is the centre for the water sports activities on the loch; water skiing, canoeing and sailing. The loch is also stocked regularly with brown and rainbow trout and fishing, by permit, is possible from the shore and by boat.
To the south of the loch lies Ben Vorlich, a steep sided pyramid shaped peak. At 3,232 feet, this is a popular climb and the views from the top are spectacular. Just east of Lochearnhead, on the south side of the loch, is Edinample Castle, built by 'Black' Duncan Campbell of Glenorchy in 1584. Further east is Ardvorlich House, home to the Stewarts of Ardvorlich from 1580 (rebuilt in 1790).
Loch Earn is unusual in that it has its own apparent 'tidal system', or seiche, caused by the action of the prevailing wind blowing along the loch. This wind pressure on the surface causes the water level to build up at one end of the loch. As with all damped mechanical systems, applied pressure can result in an oscillation, and the water will return to the opposite end of the loch over time. In the case of Loch Earn, this has a period of 16 hours and the effect can be measured, but is difficult to observe. The resulting currents can create complex turbulence patterns, as higher layers of warmer waters mix with the lower lying colder waters of the loch.
Accommodation and activities
Hotels on the loch include at the Eastern St Fillans end of the Loch: Achray House hotel and lodges, Drummond Hotel and the Four Seasons hotel. and at the Western Lochearnhead end of the Loch: Kings House Hotel, Clachan Cottage Hotel, The Boathouse, Briar Cottages and the Lochearnhead Hotel.
- McNaughton, D,(1988) “The History of Upper Strathearn”, Jamieson & Munro.
- Murray, J, 1906. An investigation of the seiches of Loch Earn by the Scottish Lake Survey, Part 2, Preliminary limnographic investigations on Loch Earn. Trans. Roy. Soc. Edinb., 45, 387-396.
- MacManus, J. and R. W Duck, Internal seiches and subaqueous landforms in lacustrine cohesive sediments, Nature, 334, 511-513, 1988
- Victoria Cottage circa 1895, Achray House hotel and lodges. Retrieved 2010-01-04.
- Drummond Hotel. Retrieved 2010-10-04.
- Four Seasons hotel, Perthshire. Retrieved 2010-01-04.
David B. McNaughton, The History of Upper Strathearn, Jamieson & Munro (1988)