Off limits to visitors but visible from across its canal-ringed island, Breda's castle dates to at least 1300. It was expanded by the Nassaus in the 15th and 16th centuries then rebuilt by Willem of Orange from the 1780s. However, by the time it was finished he'd moved to London to become King William III of England. The 3rd floor was added in 1828 when the building was converted into a military academy, a role it still serves.
To see inside you'll have to book in advance for the Tourist Office's Historic Kilometre walking tour (in Dutch), usually held the last Sunday each month.
From across the canal, the visual highlight is the Spanjaardsgat water bastion-gate.
