Combined with natural bodies of water, the Waterline could be used to transform Holland, the westernmost region of the Netherlands and adjacent to the North Sea, almost into an island.

Early in the Eighty Years' War of Independence against Spain, the Dutch realized that flooding low-lying areas formed an excellent defence against enemy troops.

In the latter half of the war, when the province of Holland had been freed of Spanish troops, Maurice of Nassau planned to defend it with a line of flooded land protected by fortresses that ran from the Zuiderzee (present IJsselmeer) down to the river Waal.

Under the water level additional obstacles like ditches and trous de loup (and much later, barbed wire and land mines) were hidden.

In 1794 and 1795, the revolutionary French armies overcame the obstacle posed by the Dutch Water Line only by the heavy frost that had frozen the flooded areas solid.

At the advent of World War II, most of the earth and brick fortifications in the Water Line were too vulnerable to modern artillery and bombs to withstand a protracted siege.

While the Dutch army was fighting a fixed battle at the Grebbe Line, German airborne troops captured the southern approaches into the heart of "Fortress Holland" by surprise, the key points being the bridges at Moerdijk, Dordrecht and Rotterdam.

When resistance did not cease, the Germans forced the Dutch into surrender by aerial bombing of Rotterdam and threatening the same for Utrecht and Amsterdam.

In 2010, one of the forts on the Line Bunker 599, was opened as a publicly accessible work of art that was created through a cooperation between RAAAF and Atelier de Lyon.