Next month I will be travelling on a train between Edinburgh and London, just me with ds1 (4yo) and ds2 (2yo). The train journey is about 4 1/2 hrs so I'd like to break it up. The train stops at Newcastle, York and Peterborough.
Ideally I'd like to be able to jump off the train with them, visit somewhere good, not too far from the station and then get the train the rest of the way back. I was thinking of going to the NRM in York (or perhaps just the model railway museum, which I know is just next to the train station). Any other possibilities?