Grogley (& Hustyn) Woods are near Bodmin, in Cornwall, has a range of good downhill and Enduro MTB runs, with roots and small to medium sized jumps.
Tucked away, not the easiest to find and no facilities, but the trails are good fun.
You must wear a helmet (and body armor is recommended).
Walk the tracks before you ride them for the first time.
Have a phone and take the grid reference number from the noticeboard in the car park.
Route distance: Downhill