Rannoch Moor

Where it sits. Rannoch Moor is a roughly triangular expanse of blanket bog, lochans and bare granite covering some 130 square kilometres at an average height of around 300 m, bounded by Glen Coe to the west, the Black Mount hills to the south, Loch Rannoch to the east and the wilds of Corrour to the north. The A82 clips its western edge between Bridge of Orchy and the Kingshouse; the West Highland Line crosses the middle of it; and between those two thin threads there is almost nothing — no village, no road, no shelter, and in poor visibility very little to navigate by.

How it was made. The moor sits on a granite pluton, a mass of igneous rock intruded some 400 million years ago and later stripped bare by ice. During the last glaciation this basin held a great ice dome that fed glaciers outward into the surrounding glens, so the moor is in a real sense the place the ice came from rather than a place the ice merely passed through. When the ice went, poor drainage over impermeable rock allowed peat to accumulate; depths of several metres are common. The result is a mosaic of bog pools, sphagnum lawns, heather, bog myrtle and drowned pine stumps — the remains of a forest that grew here thousands of years ago and was killed as the peat rose.

Crossing it. The railway is the moor's great engineering story. When the West Highland Line was pushed through in the early 1890s, engineers found the ground would not bear a conventional embankment, so sections of the formation were floated on a raft of brushwood, turf and ash — a technique borrowed from marsh railways elsewhere but rarely attempted at this scale in Britain. The line still rides on it. Two stations serve the moor: Rannoch, reachable by a long dead-end road from the east, and Corrour, at 408 m the highest mainline station in Britain and famously unreachable by any public road at all. The West Highland Way crosses the moor's western edge on the old military road, and the Kingshouse Hotel at the far end has been sheltering travellers since the eighteenth century.

On screen. The moor is used constantly as shorthand for wilderness. In the Potter films it supplies landscape plates along the Hogwarts Express route and open-country material for the fugitive sequences of Deathly Hallows – Part 1 (2010); the train shots people associate with Glenfinnan were part of a longer filming programme along this whole line. Corrour station is better known for a different film entirely — the walk into the countryside in Trainspotting (1996) was shot there, which is why a remote Highland platform sometimes attracts visitors quoting dialogue about being colonised by wankers. Keeping the two straight matters: Corrour is Trainspotting, Glenfinnan is Potter, and the moor between them has served both.

What you actually see today. From a car on the A82 the moor reads as a vast, almost lunar sweep of brown and grey with the Black Mount rising on the left and Lochan na h-Achlaise mirroring the sky on the right — one of the most photographed roadside views in Scotland. From a train it is far better: twenty minutes of nothing but water, peat and distant hills, with no road in sight. On foot it is serious ground. There are no waymarked circular routes across the interior, the peat hags make straight-line walking impossible, and rescue is a long way off. Loch Ossian, near Corrour, has a youth hostel on its shore and offers the most approachable taste of the moor's interior.

Getting there and timing. The A82 from Glasgow reaches the moor in about two hours. The Glasgow to Fort William train crosses it several times daily and is by far the best way to see it. Rannoch station is a 40-minute drive from Kinloch Rannoch; Corrour has no road access. Late spring gives long light and dry-ish ground; autumn turns the moor gold and russet. Winter can be extraordinary and is also when the A82 closes most often for snow. Midges are severe from June to September and there is no escaping them in still weather.

Practical notes. Carry more clothing than you think you need, plus map and compass, and treat the weather forecast as advisory rather than reliable — conditions here differ from both Glen Coe and Loch Rannoch. There is a station café at Corrour and a hotel at Kingshouse; otherwise nothing. Mobile coverage is minimal. Stay on tracks where they exist, both for your own sake and because the bog surface is fragile and slow to recover.