So I want to go and camp for a couple nights with a group of friends sometime in the summer. Gear and techniques are all sorted, the only thing left to deal with is the location.

We're looking to :
Start a small campfire and cook stuff (at night)
and MAYBE trap some small game

Can anyone recommend any good locations within a >2.5 hour train trip from greater london? Specifically within >2.5 hours of Watford,

Thanks in advance.