Marehill Quarry is an abandoned sandstone mining site, which first opened at the end of the 19th century. The quarry was extracting fine grade sand for the iron industry of the midlands up until the 1940’s. After World War Two the caving system became a mushroom farm for a short period and then remained abandoned until the Sussex Wildlife Trust took over the site in 1998. The cave system here is an ideal environment for animals to roost hence there are various species of bats, moths and spiders to be found.