Càrn Mairg

Càrn Mairg supports a fascinating range of Highland wildlife adapted to the changing altitude and exposure. As you climb from Glen Lyon, you'll pass through zones of heather moorland where red grouse burst noisily from cover and red deer graze the slopes. Curlews call across the lower ground in spring and summer, their haunting cries echoing through the corries.

Higher up, the vegetation transitions to montane heath with hardy grasses, sedges, and dwarf shrubs that can withstand the harsher conditions. Watch for ptarmigan above 900 metres—these mountain specialists change their plumage with the seasons, becoming white in winter for camouflage against snow. Ravens patrol the ridges, their acrobatic flights accompanied by distinctive croaking calls.

Golden eagles hunt across these Perthshire hills, and you might spot one soaring on thermals in the distance. The relatively drier eastern climate supports different plant communities than the wetter west coast mountains.

The Càrn Mairg circuit demands thorough preparation and respect for its length and commitment. Navigation skills are essential—while the route is well-established, deteriorating visibility can make the multiple summits and connecting ridges confusing without confident compass work. Carry full hill kit regardless of the forecast: weather at 1041 metres can be dramatically different from conditions in Glen Lyon.

The 18-kilometre distance means you'll need adequate food and water—streams are available on much of the route, but carry a filter or purification tablets. The boggy sections can be energy-sapping, so allow extra time and consider gaiters. Mobile signal is unreliable throughout, so inform someone of your route and expected return time. Start early to ensure you complete the circuit in daylight, particularly outside midsummer.

The combination of distance, ascent, and variable terrain makes Càrn Mairg more serious than its modest 4/5 difficulty might suggest.