Residence and administrative seat of the Guelphs.
Today's Guelph Castle is the impressive remnant of earlier residences, which lost its unique splendour with the death of Erich II and from then on was only an occasional place of residence for the sovereign. In 1849, a fire destroyed the south wing of the palace, which was never rebuilt.
Two original Renaissance chambers with wall paintings covering the entire area are still preserved, the like of which cannot be seen anywhere else in Germany. The rooms can be visited on a guided tour.
Today, in addition to the municipal archives, the municipal library and the district court, the castle also houses the municipal museum, which celebrated its 100th anniversary in 1998.