Arming the forts

Since most of the forts served as an ‘access post’, their purpose was to stop enemy troops from attempting to break through the Defence Line via passable sections in the inundation. So most of the forts were armed only with light artillery (six and seven calibre) in armoured disappearing capolas for close-range fire. Exceptions were forts and defence works situated at strategically important locations: Pampus, Diemerdam, Durgerdam, IJmuiden, Velsen and Spijkerboor. These were fortified with heavier artillery (10 to 24 calibre) often placed in armoured revolving turrets. Each fort was also armed with machine-guns for close-range defence. The 'Kringenwet' (Circle Act) was in effect from 1853 for defence works in general to keep the field of fire free. Under this law, three imaginary rings existed around each fort within which strict building restrictions applied. Only wooden structures were permitted within the so-called small ring (up to 300 metres). In the middle ring (300 to 600 metres) foundations had to be made of brick. The least restrictions applied to the outermost ring (600 to 1000 metres); however, there too, building was subject to permits, as it had to be possible to knock down all structures within the ‘restricted rings' within the shortest possible timeframe. The ‘Kringenwet’ remained effective up to November 1963; as a result the landscape has remained unobstructed in many places.