With such a large empire I've always found it strange that they had such a hard time with Scotland, eventually giving up completely and building Hadrian's wall.
Was it just the case that there wasn't much useful north of the wall and that it wasn't worth the time or effort required to conquer the whole of Britain?
hi! not discouraging other responses, but you can get started on these
How close were the Romans to completely conquering England, Wales & Scotland?
Why was the Roman Empire able to take England but could not push into Scotland?
Hadrian's Wall