This castle was built between 1677 and 1686 by William of Nassau-Odijk. The interior is by Daniël Marot. In 1713 the Treaty of Utrecht was signed here. The building is now used as a conference centre (temporary exhibitions). On either side of the alley which leads to the castle, you can see the buildings of the Moravian Brothers community, whose members are disciples of Jan Hus, a Czech priest who was burned alive in 1415.