Probably my favourite British mammal is the roe deer.
This pair were crossing a field at West Knighton.
A few minutes later I caught up with them again.
As always the area produced a good list of mammals with sika deer as well as roe, along with rabbits, grey squirrels, lots of badger evidence (including one dead animal) and these hares:
And here's some footage of the hares shot at 60 fps, to slow them down a bit.