FORT NEAR SPIJKERBOOR

Fort bij Spijkerboor is the largest fort of the 42 defense forts surrounding Amsterdam. The fort is especially unique due to the still present large armored dome containing two 10.5 cm quick-firing cannons, at the time the most powerful in the Netherlands. The fort served to seal off and defend the access routes*) formed by the Western Beemster Ring Canal with the roads and paths running alongside it. The fort has two floors due to the height of the dike that needed to be defended.
In 1975, the fort was sold by the Ministry of Defence to the Public Domain Service. In 1992, this service sold the fort to Staatsbosbeheer. The fort is currently leased by the Society for Nature Monuments. It has been restored and can be visited.

Fort bij Spijkerboor is part of the Amsterdam Defense Line, a defensive line located 15 to 20 kilometers around Amsterdam. The line was constructed between 1880 and 1914. The line is 135 kilometers long and consists of 46 forts and batteries, countless dikes, dams, and locks.
The terrain around Amsterdam consists of polders and drained lakes and is generally very wet and low-lying. In the event of a hostile attack, the polders would be flooded by allowing a large amount of water to flow in, resulting in a water level of 20 to 30 centimeters. This forced the attacker to advance over the narrow existing land roads and polder dikes. The defender had to exert considerable effort to establish defensive works at these access points.
In 1996, the Amsterdam Defense Line was included in its entirety on the UNESCO World Heritage List.

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