Defence Line of Amsterdam – Arthur van Beveren Photography

Fully armoured casemate. — Fort bij Edam

View from the observation turret. — Fort bij Vijfhuizen

A unique armoured caponnière was erected to cover the deep ditch of the fort. — Fort bij Hoofddorp

To close the gaps between the forts, several fortified batteries were built in between. — Battery near Veldhuis

Seperate toilets for (non)commissioned officiers and the sick. — Fort bij Uithoorn

Observation turret on the backside of the fort. — Fort bij Waver-Amstel

Double casemate for covering the back of the fort. — Fort bij Waver-Amstel

Early 20th centry art work to make the inside of forts more livable. — Fort bij Spijkerboor

Casemate for a retractable gun turret. — Fort bij Waver-Amstel

Observation turrets on top of the fort. — Fort bij Waver-Amstel

Military engineering building. — Fort bij Uithoorn

Observation turret. — Fort bij Spijkerboor

The fort is now in use as a spa. One of several examples of modern reuse. — Fort aan de Nekkerweg

Krupp double barreled rotatable gun turret. — Fort bij Spijkerboor

Machine gun positions. — Fort bij Spijkerboor

Machine gun position. — Fort bij Spijkerboor

[gallery_desc]2014 marks the 100th anniversary of the beginning of World War One. Neutral Netherlands didn’t see any fighting on its own soil. It did however see thousands of refugees and prisoners of war. It also prepared for a war itself. 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. The defence was based on the flooding of lowlands and protection of high parts likes dikes and railways. At the beginning of World War One, the Netherlands remained neutral, and did not finish the defence line. New strategical insights during the war showed that aeroplanes, and mobile fronts made the forts obsolete. During the interbellum, only small concrete bunkers were added to vulnerable areas in between the forts. The entire line is now protected UNESCO World Heritage. The forts are environmental safe havens. They once were intruders in a quiet landscape. Nowadays they’re part of it themselves.[/gallery_desc]