Wander with me for a moment in time. We are at Vesting Nieuwersluis. This fort stands guard where the Amsterdam-Rijnkanaal meets the Vecht river. It is west of Nieuwersluis in the Honderdsche Polder.
The Vesting Nieuwersluis’s purpose was clear. It protected the damsluis in the Vecht. This prevented Zuiderzee and Lek water from mixing during inundations. It secured the schutsluis to channel Vecht water to Amsterdam’s inundations if needed. The fort defended the Vechtdijken. These were the roads to Amsterdam. It covered the Utrecht-Nieuwersluis railway and the Nieuwersluis-Amsterdam railway. It covered the area between Fort Spion and Fort Tienhoven.
In 1629, a small outpost stood near Nieuwersluis. It was named after the sluis in the Nieuwe Wetering. More fortifications arose in 1673. As a replacement for the Vesting Nieuwersluis, the southwestern part was dug into a fort with a tower between 1849 and 1851.
A.L.W. Seyffardt wrote in 1887 about the fort’s role. He stated that it could make life unpleasant for any enemy penetrating the river. Originally, there were plans to connect the Amsterdam position to the Nieuwe Hollandsche Waterlinie at Nieuwersluis. This would have made Nieuwersluis a vital part of Amsterdam’s defense. However, the outer perimeter ran over Abcoude to Weesp. This made Nieuwersluis a kind of outpost, securing the Rijnspoor and the Vecht.
Around 1951, a kokerschietbaan was likely built. It served the Bescherming Bevolking and/or Nationale Reserve for handgun practice. Similar ranges existed at Fort bij Edam and Fort bij Spijkerboor. In 1964, half of the bomb-free barracks’ ground floor transformed into a command post for the Bescherming Bevolking.
The landscape around Vesting Nieuwersluis remains open polder. The Merwedekanaal, broadened in the 1930s, became the Amsterdam-Rijnkanaal in 1939. Vesting Nieuwersluis is now a state monument and part of a UNESCO World Heritage Site. It sits at the Stelling Boterkade. It is between Nieuwe Ter Aa and Nieuwersluis.