One or two day trips near Glasgow

I'll be visiting the inlaws for a week soon but might find time to get in a one or two (maybe even three at a push) day trip somewhere up in the north of britain. I don't like round trips so usually aim to do from one rail station to another. So does anyone have any suggestions. The ideal would be a fairly well established route but for a couple of days near glasgow. For a longer trip I'll go further on the train before starting but a shorter trip really should be pretty close (no point sitting on a traing for 6 hours for a one day trip)

Any suggestions?

On the train you can head up to Arrochar/Tarbet and bag various Arrochar Alps after a short walk from the station and come back from the next stop up at Ardlui (or the other way around).  Not far up the line from glasgow so scenic though the train trip is you don't waste too much time on it.

Pete.

A few more options further north Crianlarich to Tyndrum, or Tyndrum to Bridge of Orchy (or vice versa) using the West Highland Way. A bit more remote and further afield Corrour to Rannoch Station.

Slainte

Lindsay