Wassenaar is a town in the western Netherlands, in the province of South Holland.
An exceedingly affluent suburb of The Hague, Wassenaar lies 10 km (6 mi) north of that city on the N44 highway near the North Sea coast. It is part of the Haaglanden region. The municipality covers an area of 62.50 km², of which 11.65 km² is covered by water. Inhabitants of Wassenaar are called Wassenaarders