Greasley Castle was originally a large medieval fortified manor house, founded by Hugh fitz Ralph. In 1340, Nicholas de Cantilupe founded the stone castle, when he was granted licence to crenellate but sadly the site has now been completely dismantled. An 18th century house, with the remains of an underground passage in the basement, stands on the site of the upper ward. In the lower ward, incorporated in later farm buildings, are the only substantial masonry fragments. Defended by a wide ditch, with a counterscarp bank, stands a length of curtain wall, which was flanked by a round angle tower. To the south of the main wards, is a large banked and ditched enclosure, with a series of large rectangular fish-ponds. 5 miles north-west is Codnor Castle and 5 miles north-east is Annestey Castle.