Ringwork

A ringwork is a form of fortified defensive structure, usually circular or oval in shape. Ringworks are essentially motte-and-bailey castles minus the motte. Defences were usually earthworks in the form of a ditch and bank surrounding the site. Ringworks originated in Germany in the 10th century as an early form of medieval castle and at first wer...
Found on http://en.wikipedia.org/wiki/Ringwork

Ringwork

A type of circular earthwork consisting of rampart and external ditch broken by an entrance. Constructed mainly by the Normans in Britain. Romanesque In England called Norman, a style of architecture influenced by the Roman. Current in the eleventh to twelfth centuries. Some Anglo-Saxon architecture is called, misleadingly, pre-Conquest Romanesque....
Found on http://www.digital-documents.co.uk/archi/gloschur.htm

Ringwork

An earthwork castle which has no identifiable strongpoint or motte.
Found on http://great-castles.com/glossary.php

Ringwork

circular earthwork of bank and ditch
Found on https://www.encyclo.co.uk/local/20402

Ringwork

circular earthwork of bank and ditch
Found on http://www.encyclo.co.uk/local/22129

Ringwork

Circular earthwork of bank and ditch.
Found on http://www.castlesontheweb.com/glossary.html

Ringwork

Circular earthwork of bank and ditch.
Found on http://www.encyclo.co.uk/local/20018

ringwork

small enclosure with a high rampart around it
Found on http://www.castles-of-britain.com/glossary.htm
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