This manor house (Hofwijck) surrounded by water was built in the middle of the 17C according to the design of Constantijn Huygens, secretary and adviser to the Orange family, who wanted to retire from the court and enjoy the peace and quiet here. His son Christiaan, inventor of the pendulum clock, a physician and an astronomer of international renown, also spent the end of his life there. The museum's collections provide an insight into this illustrious family.