Not as remote as this...
Burton Fell
It's right in the middle of the Warcop training ground off the A66 between Brough and Appleby. Our cottage is nearby and my grandad used to take me and our kid on tours around the lanes inside the danger zone when we were little. When the red flag is down you can use the rights of way and go see loads of stuff that's been shot to bits with 50cal. There's an old ruined house on the edge of the danger zone called Tarn House, you can't get to it when the red flag's up but it's a really interesting building. Actually there's quite a lot of really nice hilly land out of bounds at Warcop, the danger zone is vast.