A refuge castle[1] or refuge fort (German: Fliehburg, also Fluchtburg, Volksburg, Bauernburg or Vryburg) is a castle-like defensive location, usually surrounded by ramparts, that is not permanently occupied but acts as a temporary retreat for the local population when threatened by war or attack.
In Europe a multitude of large protohistoric sites surrounded by earthworks has been uncovered by archaeological excavations, many over 100 metres in diameter, that are understood to be refuge castles.
Similar ringwork (Ringwall) systems were built by the various Germanic and Slavic tribes, the latter until well into the Middle Ages period.
Refuge castles of this type belonged to unprotected farming communities and offered protection to the population of the local region in case of a hostile attack, whilst the settlements themselves usually fell victim to plundering and destruction by the aggressors.
Their fortifications generally had little in common with the castles erected by the nobility as residences, but often consisted just of earthworks and wooden palisades sited in easily defensible locations on hilltops or spurs.