What is a “motte-and-bailey” an example of?

The story behind the answer

A motte-and-bailey combined a raised earthen mound (the motte) topped with a wooden or stone tower and an enclosed courtyard (the bailey) surrounded by a palisade and ditch. The elevated motte gave defenders line-of-sight and a last refuge, while the bailey housed troops, workshops, and supplies—an efficient, modular design for early medieval warfare.

Originating in 10th-century France, the form spread rapidly after 1066 as the Normans used it to secure England and Wales. Built quickly from timber and earth, these strongpoints established control over newly conquered regions before being replaced or upgraded to stone keeps. Today, many survive as grassy mounds and rings, echoed in place names like “Castle Hill.”