Norfolk, England
Bailey St & Castle Sq, Castle Acre, King's Lynn PE32 2AG
A Norman motte-and-bailey castle in ruins, cared for by English Heritage and free to enter, in the Norfolk village of Castle Acre. No notes or visitor reviews are logged for this listing, so there's very little to go on for what a visit here actually feels like.
The earthworks and Bailey Gate remains - the main survivals at a site with limited documentation currently available.
With no visitor-reported detail available, check English Heritage's own site page for access, parking, and current condition before visiting.