Marehill Quarry is a 1.1-hectare (2.7-acre) geological Site of Special Scientific Interest east of Pulborough in West Sussex.

[1][2] It is owned and managed by the Sussex Wildlife Trust[3] and is a Geological Conservation Review site.

[4] This disused quarry is the type locality for the Marehill Clay, a member of the Sandgate Beds, part of the Lower Greensand Group, which dates to the Lower Cretaceous between 145 and 100 million years ago.

[5] It has caves which are used for hibernation by several species of bats, including Natterer's, whiskered and Daubenton's.

[3] There is no public access to the site.