Stelling van Amsterdam

A combination of inundation and posts to protect Amsterdam date back as far as 1629, when these were prepared against a planned but later cancelled attack from the south by the Spanish general Ernesto Montecuccoli during the Eighty Years' War.

Another water defence line was prepared in the south in 1672, the Rampjaar, but the invaders failed to get past the Old Dutch Waterline.

[3] When the English invaded Holland in 1799, a water defence line was created north of Amsterdam, led by engineer Cornelis Krayenhoff.

In 1800, the Line of Beverwijk [nl] was created led by Krayenhoff to the west of Amsterdam, fearing another invasion by England.

In 1805, Krayenhoff was tasked with creating a new defence line, because King Louis Bonaparte feared annexation by the First French Empire.

The invention of the high-explosive shell and the percussion fuze, which allowed ordnance to explode on impact and dislodge brick fortifications easily, necessitated a change from masonry to concrete forts.

The motorway also goes under the Ringvaart at Roelofarendsveen, which makes the inundation of the Haarlemmermeer Polder and thus the future use of the Stelling no longer possible.

Engineer Cornelis Krayenhoff was involved in all defence lines around Amsterdam since 1787, in particular the Posts of Krayenhoff named after him.
Fort south of Spaarndam.
Muizenfort in Muiden .
Fortifications on Pampus island.