Glen Lyon, in Highland Perthshire, is one of the longest glens in the Scottish Highlands, and runs west from the village of Fortingall, reaching thirty four miles into the mountains and ending just past Loch Lyon.
The glen was the home of the Campbells of Glen Lyon. Members of this clan formed most of the force that carried out the Glen Coe massacre.
The glen is the home to a number of small communities. Fortingall, at the eastern end, is an Arts and Craft village.
Just to the west of Fortingall is McGregor's Leap, where Gregor Roy is said to have leaped across the river to escape from the hounds of Sir Colin Campbell of Glenorchy, Laird of Breadalbane.
The hamlet of Bridge of Balgie, about half way up the glen, contains the only shop, the Glen Lyon Post Office and Tea Room.
A single road runs along Glen Lyon, running along the northern side of the River Lyon. The eastern end of the road can be reached along a minor road from Fearnan (near the eastern end of Loch Tay), or by turning off the B 846 at Keltneyburn, west of Aberfeldy.
Two minor roads cross the mountains on the southern side of the glen. The valley road leaves the Glen west of Pubil (just below Loch Lyon) and heads south towards Kenknock in Glen Lochay. Finally a road runs south from Bridge of Balgie, in the centre of the valley, and crosses the mountains to reach the western end of Loch Tay.
The Glen is surrounded by Munros. At the eastern end the entrance to the glen is formed by the Ben Lawers group in the south and a ground that peak at Carn Mairg in the north. The high ground continues all along the glen and the head of the glen is surrounded by 1,000m high peaks, including Beinn Heasgarnich, Creag Mhor, Beinn Dorain, Beinn Achaladair and Beinn a' Chreachain.