Park Clingendael is one of The Hague's loveliest green spaces, an old estate landscape of lawns, woodland, water, and formal garden elements. Its most famous feature is the Japanese Garden, a delicate early-20th-century garden that opens only for limited periods to protect the planting. When it is open, it is worth planning around.
Even outside Japanese Garden season, Clingendael is a fine place to walk, especially if you want a quieter alternative to Scheveningen or the city centre. The park's paths make it easy to spend an unhurried hour among trees and ponds. Bring a picnic if the weather is kind.