West of the A9, East of the Great Glen, North of Rannoch, inc. Nevis, Mamores, Ben Alder and Creag Meagaidh
Aonach Mor is unusual for Scotland in that it offers superb lift served off-piste skiing and boarding . A few of the obvious lines are described below, but many more lines have been skied or boarded, and are detailed in the guidebook Scottish Offpiste Skiing & Snowboarding: Nevis Range & Ben Nevis by Kenny Biggin, published in November 2013. You'll need to buy the book to find out about them!
Ben Alder is a complex mountain with a large plateau, clearly visible in the distance from the A9 when heading south. The approach is long, and may deter most, but in relatively dry conditions, most of it can be done by mountain bike, taking the sting out of a day trip. The lines described here are in the remote Garbh Choire, on the east face of the mountain. On a clear day, you should be able to see into the corrie from Dalwhinnie, which should help decision making as to whether to make the long journey or not.
Ben Nevis is one of the most popular mountains for gully skiing in Scotland.
Other than those described below, gully / face descents known about include:
The large East face of Carn Mor Dearg is well seen from Aonach Mor and offers fantastic face skiing in the right conditions. It often holds onto snow well into the spring, and is worth the effort to get to.
There are no definite lines as such - it's a case of ski anywhere the snow conditions allow. The main bowl below the summit offers the biggest and best options, but the bowl to the north of Carn Dearg Meadhonach looks good as well.
Coire Ardair is one of the most spectacular corries in Scotland, with the "Post face" rising 400m above Lochan a' Choire. From the skiers point of view, there's a great high level tour round the tops of the corrie, but there are some fantasctic long descents to be had into Coire Ardair itself.
The fine peak of Stob Ban is dwarfed by it's lofty neighbours, but it is a fine prominent peak. The East facing cliffs above Coire a' Mhusgain offer some interesting looking descents, but the main draws are the deep gullies (South Gully and North Gully) either side of the main summit.