In reply to John Clinch (Ampthill):
> Worth pointing out that you if coming from Southern England a Friday night train can drop you off saturday morning and the Sunday night train will have you at Euston for 7 Monday morning. A colleague did this a few weekends back. The supplement for a sleeper isn't huge. She spent Saturday night in Corrour Youth Hostel
Yeah, I've done long weekends that way once or twice. Helps to have an office with a shower, though.
But generally, there's loads of hills in Scotland that are accessible from the train - using public transport from London it's probably actually more convenient to do a long weekend in the Highlands than in North Wales or the Lakes. Off the top of my head:
* pretty much every stop North from Arrochar on the West Highland Line has some walkable hills
* Blair Atholl is a good jumping off point for the hills around Glen Tilt and Glen Tarf
* Dalwhinnie for the hills either side of Drumochter
* Newtonmore for the Monadh Liadh munros
* there's a bus up from Aviemore to the ski centre, although I can't remember how conveniently it meets the sleeper
Achnashellach and Glenfinnan both have good options too, although they're a bit less convenient for timings with the trains.