Lydstep Caverns is a sandy beach located west of Lystep Head, and is only worth visiting on a very low tide - otherwise it's mostly underwater. The beach is backed by high limestone cliffs and is a popular venue for climbers. As its name suggests, it has some spectacular caves and arches and it's a good beach for fossil collecting - corals being very common.
Parking is either at Lydstep Head or Skrinkle Haven. Lydstep Head is the closest one, and is reached by turning off in Lydstep village onto a byway signposted as a no-through road. After about 300 yards along this very bumpy lane, a turning on the right leads to the (free) National Trust car park at the top of the hill. From here, take the coastal path westwards to the bottom of the valley, where the way onto the beach can be seen.