Poelberg, The Netherlands

The Poelberg is a 0.5 meter high vliedberg located near the Zeeland village of 's-Heer Arendskerke. Archaeological research showed that before it was excavated in 1875, the mountain consisted of two mounds, the largest of which had a diameter of fifty meters and the smallest a diameter of thirty meters. The mounds probably served as the main castle and outer bailey and were both surrounded by a moat twenty meters in diameter. Both castles were connected by a wooden bridge that was built around 1150. There was probably a brick residential castle on top of the highest motte.

Wikipedia