Moulton Castle, also known as King's Hall Park, is a medieval earthwork and scheduled monument situated 1.5 miles (2.4 km) to the south of Moulton, Lincolnshire, England. It probably dates from the twelfth century. It was owned by Thomas de Moulton in the early thirteenth century and it was during this period of unrest when the fortifications were most likely constructed. It remained under occupation by the Moulton family until at least 1313. It has been reported that some of the stone from the castle was used to build part of the church porch at nearby Holbeach.