Brittenburg

Brittenburg was a Roman ruin site west of Leiden between Katwijk aan Zee and Noordwijk aan Zee, likely identical to the earlier Celtic Lugdunum fortress[1]. First mentioned in 1401, it was uncovered by storm erosion in 1520, 1552, and 1562, then entirely eroded away[1]. Archaeological evidence indicates it served as a Roman naval base and fortified military granary at the Rhine estuary[2].