Knockan Crag

Knockan Crag stands in the North West Highlands Geopark near Ullapool, a rocky hill where grey Moine schists sit above pale Cambrian limestone. The site lies 21 kilometres north of Ullapool in the Assynt region of the Scottish Highlands. Geologists once argued fiercely over how older schists could rest above younger rocks, a debate known as the Highlands Controversy. Roderick Murchison and Archibald Geikie thought the sequence was correct, while James Nicol and Charles Lapworth believed a fault had pushed the older rocks westwards. The dispute ended when Ben Peach and John Horne proved the presence of a thrust fault in 1907. The crag is now a national nature reserve managed by NatureScot. An interpretation centre explains the geology and the controversy, while three marked trails lead visitors to key viewpoints. Artworks such as Joe Smith’s ‘The Globe’ and Susheila Jamieson’s ‘Pipeworm’ show how the landscape has inspired artists. The reserve’s limestone areas support mountain avens and rock sedge, while schist soils carry wet heath and blanket bog. Nearby Lochan an Ais attracts red- and black-throated divers in winter and spring. Birds like kestrel, raven and ring ouzel live on the crag, alongside songbirds and meadow pipits. Scottish red deer often cross the site, and the plateau above shows sharp contrasts between limestone knolls and peat-filled hollows. The reserve forms part of the wider Knockan Cliffs Site of Special Scientific Interest and the North West Highlands Geopark. Its geological importance is recognised internationally, making it a key place for understanding Scotland’s ancient earth movements.