Defence Line of Amsterdam-Fort in de Botshol

The UNESCO World Heritage Site known as the Defence Line of Amsterdam (in Dutch named Stelling van Amsterdam) is a 135 km long ring of fortifications around Amsterdam, consisting of 42 forts located between 10 to 15 kilometers the centre, and lowlands that can easily be flooded in time of war. The flooding was designed to give a depth of about 30 cm, insufficient for boats to traverse. Any buildings within 1 km of the line had to be made of wood, so that they could be burnt and the obstruction removed.

The Stelling van Amsterdam was constructed between 1880 and 1920. The invention of the aeroplane and tank made the forts obsolete almost as soon as they were finished. Many of the forts now are under the control of the town councils and the nature department, and may be visited. Monuments Day, on the second Saturday in September, is the ideal day to visit as entrance is free.

The Fort in the Botshol is the only Defence Line fort whose defensible earthwork from 1895 has been preserved. The soggy peat soil around Amsterdam made it necessary to first strengthen the terrain with large amounts of sand. Also unique is the bridge behind the fort watchman's house, whose centre piece could be removed in times of danger.

The Fort in the Botshol defended the accesses formed by the south quay of the Botshol and the permanently dry strips of land in the Noorder-Zuiderpolder.

The Fort in the Botshol lies in a rich nature reserve and is only open during Stellingmaand (Defence Line Month) in September.

More information is available here.