What is a waterline?
During the war, the water lines were a very good means of defending our country and our cities against the attackers. It is quite a complex system in our landscape. In short, areas especially along the rivers are flooded with the aim of stopping the enemy. The Netherlands has eight water lines, of which the old Dutch water line and the New Dutch water line are the best known. The New Dutch Water Line is actually the same as the Old Dutch Water Line, only extended further so that the city of Utrecht is also defended by the line.
How does a waterline work?
A water line consists of many sluices and weirs, which can be used to initiate inundation. Inundation means the deliberate flooding of land; this was first done in Alkmaar in the year 1573. This was done to keep the enemy at bay, as walking across the land became impossible and the water was left about 40 cm on the land, making it practically impossible to navigate. A water line consists not only of flooded land but also of many fortified cities and forts. It is, of course, impossible to protect the land with water alone; furthermore, it is impossible to flood all areas thoroughly. To close these weaknesses, armed fortified cities and forts are located within the line.
Which water lines are there in the Netherlands?
In the Netherlands we have eight lines that defend our country and our cities. As mentioned above, the most well-known are the Old and New Dutch water lines. In addition, there are other lines that still support the (New) Dutch water line. The Netherlands has the following water lines:
- Frisian waterline, defended the western part and the capital Leeuwarden.
- Grebbe Line, pre-defense of the Dutch Waterline.
- IJssel line, defense from the German border mainly along the river IJssel.
- New Dutch Waterline, Expansion on the Old Dutch waterline, including Utrecht.
- Old Dutch Waterline, defense of the western part of the country, from Belgium to the Zuiderzee.
- Defense Line of Amsterdam, defense for our capital Amsterdam.
- West Brabant Waterline, defense between the fortified towns of Bergen op Zoom and Steenbergen, also the oldest water line in the Netherlands.
- Southern Frontier, defense of the Belgium-Netherlands border, from Sluis to Nijmegen.

