An amazing cave system lies beneath this green space.
Discovered by Captain Sturmy over 300 years ago, Pen Park Hole is a nationally important site. It was created by rising hot waters in the late Triassic or early Jurassic period approximately 200 million years ago. Access to the cave is strictly controlled for protection and safety reasons.
Pen Park Hole is nationally important because it supports the only known example of a substantial cave-dwelling population of the crustacean Niphargus kochianus. This species is more typically found in seeps and springs of chalk aquifers, rather than in large underground lakes.