The ’Schutsluis bij Aalsmeer met inlaatduiker’ is a lock near the Aalsmeer dyke and fort. It was a part of the Defence Line of Amsterdam. Work on the Defence Line began in 1880, and the project took four decades to complete. The Defence Line was designed to defend the capital city, by allowing strategic areas to be flooded, slowing enemy troop movements. The forts were positioned near important facilities such as farms and railway lines, offering protection for important Dutch industries.
