The ’Damsluis in de Haarlemmermeerringvaart’ in Haarlem is a UNESCO protected monument. It is is a part of the defence line which was built to protect Amsterdam from invasion. The line took around 40 years to complete, with work beginning in 1880. The network of pumps, dams, and forts spans a distance of more than 130KM. The line served as a safe retreat for important government and military personnel, and was used to direct the flow of rivers, keeping the land dry on a day to day basis, and allowing for quick flooding in times of war.
