Durham Castle

Durham Castle is a Norman castle in the city of Durham, England, which has been occupied since 1837 by University College, Durham after its previous role as the residence of the Bishops of Durham. Designated since 1986 as a cultural World Heritage Site in England, along with Durham Cathedral, the facility is open to the general public to visit, but only through guided tours, since it is in use as a working building and is home to over 100 students. The castle stands on top of a hill above the River Wear on Durham's peninsula, opposite Durham Cathedral.

Source: Wikipedia