Does the train get very busy, do you need to reserves seats?
Possibly at the height of the tourist season - say July and August - just to be sure that you'll get a seat.
No, no need to book, though at the height of summer it does get busy. When you get to Kyle, walk up to the town where there is a fabulous fish and chip restaurant. It gives a good meal in the allocated time before return trip to either Dingwall or Inverness, you really will enjoy it.
If you are going in peak holiday time then I would reserve a seat. If you book online the operating company does not charge to reserve a seat. When I went (October) there were plenty of seats available.
Not really ... you don't need to reserve.. this train is more like a town bus which passes through yhe small villages. So don't worry..
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