The Old Mulgrave Castle was constructed in the 13th century as a defensive residence, replacing the earlier Foss Castle also located in Mulgrave Woods. Since then, it has been home to the de Mauley family, the Bigot family, the Radcliffe family (not that one) and Edmund Lord Sheffield, though none undertook the monumental efforts to sufficiently restore this now historic castle ruin. 

The castle was built piecemeal on a narrow ridge between the Sandsend and East Row Becks starting in 1069. By the time it was bestowed upon Peter de Mauley (a notoriously cruel henchmen of King John, believed to have killed Arthur of Brittany in 1203), there would have been an oval-shaped platform surrounded by a high curtain wall with dry moats that framed either end of the structure as well as a drawbridge and a three-story tower-like Keep.

By 1309, however, the castle was reportedly already in ruins, and deteriorated further still while it changed hands into the 17th century. In 1626, it briefly served as a semi-open-air hunting lodge, though at the outbreak of the English Civil War in 1642, Royalists forces saw tactical potential in the structure and seized it for war purposes. Upon victory, it was destroyed to prevent future use as a military base. 

Once a new Mulgrave Castle was built nearby, the Earl of Mulgrave ordered his landscaper to romanticize the ruins of the old castle, rebuilding the gatehouse towers, remodeling sections of the collapsed keep, and beautifying the surrounding woodlands. With later restorations in the 1990s, several features were further fortified and landscaped to its present condition.