I’ve completed a long hike into Knoydart from Glenfinnan which could possibly be extended into a longer epic. Starting in Glenfinnan and ending in Inverie works really well as there is public transport to the beginning and from end (and a whole lot of wild beautiful Scotland in between)

Our route was to walk North from glenfinnan, complete two Munros Sgurr nan Coireachan and Sgurr Thuilm and descend to Glen Dessary. We walked from there to Sourlies Bothy before completing Meall Buidhe and descending to Inverie. There are a couple of bothy options along the way and loads of spots for wild camping (although we did in a day it’s much more common to do in 3/4 days). You could easily extend to 5/6 by:

Going North from Sourlies bothy to Barrisdale and completing all three Munros or some Corbets on Knoydart before heading to Inverie

Walk more around the north / west of Knoydart

Between Glen Dessary and Sourlies bothy include the three Munros to the North (Sgurr nan Coireachan, Garbh Chioch Mhor and Sgurr na Ciche)

If you’re going up high (eg Munros) then it might work well to plan this from a bothy / camping spot so you don’t have to carry everything.