The Gravensteen or Gravenkasteel (English: Castle of the Counts) is a medieval castle in the city centre of the Belgian city of Ghent. The castle was built around 868 at the confluence of the rivers Leie and Lieve by the Count of Flanders Baldwin I. The Gravensteen was the seat of the Council of Flanders, you can visit the torture chambers inside.
The castle as we know now was built by Count Philip I, who went on a crusade and died in the Holy Land. That's why there is an opening in the form of a cross, right above the entrance gate in the castle's chapel. Finally the Counts moved to more luxurious housing in 1353 and the castle lost its military purpose.
Afterwards it served as the Mint, a prison and even a textile factory. Today it's a touristic attraction.