Marsco is one of the classic hills of Skye. Its distinctive pyramidal profile dominates the view southwards from Sligachan. The views from its 736m summit are great, with a panorama of the main Cuillin Ridge, close views of Bla Bheinn, Garbh-bheinn and the rest of the Red Hills, and a wide outlook over the mainland.
There are several good routes to the top. The usual one leaves Sligachan following the Loch Coruisk path for about 3km.
Leave that path to follow a patchier trail up the right bank (left side) of the Allt na Measarroch. From here there are two options. You can walk up the path a bit and then cross the burn and slog straight up the steep grassy slope of the hill's north ridge. A rather friendlier, though longer, route follows the burn all the way to the top to pick up the line of an old fence that skirts the bottom of Coire nan Laogh. The old rusty fence posts will lead you up onto the south ridge, from where it's an easy stroll to the summit. A third, shorter, way is to set out from the waterfall at the head of Loch Ainort, following the pathless and often boggy left bank (right side) of the Allt Coire nam Bruadaran to reach the old fence at Mam a' Phobuill.
When you reach the summit, take a look down the 700m steep slope to the lochans in Glen Sligachan. In the last ice age - only some 12,000 years ago - this was the point above which the Skye ice cap was centred. The ice was about 1,000m thick, covering the top of the hill you're standing on - and all those you are looking out on close by...