Which somerset gorge is famous for its limestone caves and its chesse?

Cheddar - the village, and Cheddar Gorge - the feature, holding Goughs' and Cox's Caves (show-caves).

Ironically one dairy uses the exit tunnel in commercial-rival Wookey Hole, at the foot of Ebbor Gorge only a few miles from Cheddar, to mature its own Cheddar Cheese!