Vierheulen inundatiesluis

The Vierheulen is an inundation lock from 1861, built to be able to flood the polder around the Willemstad fortress after a few roads had been raised. The lock is on the outside of the fortress. The Vierheulen is the last link in the inundation system and ensured that the water from the outer canal was let into the polder. It is a unique waterworks with four arched passageways.