Gravensteen is Ghent's great medieval castle, built by Count Philip of Alsace after he returned from the Crusades in the late 12th century. Its thick walls, battlements, and central keep still look deliberately intimidating, a reminder that the counts of Flanders wanted their power felt in the middle of the city.
Inside, the castle mixes armour, judicial history, and a grim display of torture instruments. The best part is the walk along the ramparts, where Ghent's rooftops, church towers, and canals spread out around you.