The Plofsluis consists of five concrete bins with a relatively weak floor that span the Amsterdam-Rhine Canal. The bins could store around 40,000 tonnes of sand, gravel or debris. In wartime, the floor could be blow up, so that its contents would drop into the Amsterdam-Rhine Canal. This would block the canal and prevent the inundation water from flowing out. The lock was designed in such a way that its sides would remain upright after the explosion, so that the floor could be reconstructed and the sluice could be used again. It was never actually used.
Fort 't Hemeltje dates from 1877-1881 and is the last built fort of the New Dutch Waterline. It defended a strip of land that could not be flooded and the 's-Hertogenbosch-Utrecht railway line. Nowadays, Fort bij 't Hemeltje is largely used as office space for various entrepreneurs who are active in the field of sustainability. The fort also offers shelter to (breeding) birds and bats.
There is a walking route around the fort and there is an exciting spy route with fun assignments for children. In addition, the fort is regularly open to the public, for example during Open Heritage Days.
Fort bij t Hemeltje Fortweg 11
3992 LX Houten
Lock at Cothen
Lock at Cothen
The water board uses the dam in the Kromme Rijn in Cothen to regulate the flow of water to and from Utrecht. The monumental lock alongside it (from 1865) was used during wartime to move ships past the dam. When the Waterline needed to be flooded, the commander of the inundation station at Wijk bij Duurstede first gave the order to raise the water level in the Kromme Rijn by closing off the lock with stop logs. Next, he ordered the stop logs to be removed so that a large body of water could flow from the open lock to Utrecht.