Off road sites or Pay and Play.
Mud Monsters - East Grinstead
Bures - Suffolk
Slindon - West Sussex coast
Muddy Bottom - Hampshire New Forest
Now sadly closed down forever:
Flimwell - East Sussex, clay water and gloop. Originally home of TwinAxle club.
Woodlands - Kent, near to Brands Hatch off the A20, easy fun site, flint in bottom of holes.
Penny Spring Farm - Kent, near Kent county show ground. Side slope clay chalk and lots of fun.
Rusper - Surrey - Open for very short time, enough time to break a winch and open up new tracks though.
Bethesden - Kent - Closed recently after a foolish club took chainsaws on site to clear trees themselves !!