Raesfeld is a municipality in the district of Borken in the state of North Rhine-Westphalia, Germany. It is located approximately 10 km south of Borken and 30 km east of the Dutch border.

A water castle is a castle whose site is largely defended by water. It can be entirely surrounded by water-filled moats (moated castle) or natural waterbodies such as island castles in a river or offshore. The term comes from European castle studies, mainly German Burgenkunde, but is sometimes used in English-language popular science books and websites, and is mentioned in other more academic works. When stately homes were built in such a location, or a Wasserburg was later rebuilt as a residential manor, the German term becomes Wasserschloss, lit. “water palace/manor”.