[2] The castle stood on a natural high point within the town (grid reference TL539387) and had a square Norman keep and bailey wall, forming a substantial fortification.

[2] Geoffrey de Mandeville was arrested under questionable circumstances by King Stephen in 1143, and ordered to hand over his castles, including Walden; de Mandeville initially agreed, but reneged on the agreement once released and launched a military campaign against the king's strongholds in Cambridgeshire in an attempt to free the route south to Walden.

[3] Geoffrey de Mandeville died during a siege the following year (in Burwell),[4] still not having reclaimed Walden.

Turgis had witnessed Stephen's charter by which de Mandeville was created hereditary Count of Essex,[6] and with him had witnessed the king's confirmation charter to Monk's Horton Priory in Kent.

[1] According to historian Sidney Painter, it was one of at least 21 castles demolished on Henry II's instructions.