: Early medieval strongholds featured earthworks and timber-frame "box" ramparts filled with earth, as seen in the Lusatian culture at Biskupin, Poland .
: The transition from simple refuges to complex castles occurred with the motte-and-bailey structure in the 10th and 11th centuries. Articles on the topic: "stronghold"
Historically, a stronghold (from the Old Testament Hebrew misgav ) refers to a fortified, high, or inaccessible dwelling designed for protection against enemies. Articles on the topic: "stronghold"