Nieuwezijds Achterburgwal

The Nieuwezijds Achterburgwal is a former street and canal in Amsterdam, the Netherlands.
From around 1380 to 1450 it was part of the town's defenses.
The canal was filled in in 1866, and is now Spuistraat.

In 1342 a simple earthen embankment was raised to protect the small town of Amsterdam, with a narrow canal in front of it where the Oudezijds Voorburgwal and Nieuwezijds Voorburgwal are today.
As the town grew, new defenses were built further out: the Oudezijds Achterburgwal in 1367 and the Nieuwezijds Achterburgwal in 1380.
At this time the town's population was between 3,000 and 5,000, so construction of the fortifications would have been a huge effort.
Amsterdam continued to grow, and in 1425 a broad new canal was dug further east of the town, where the Geldersekade and Kloveniersburgwal are today.
Twenty five years later the Singel was completed round the west side of the city from the IJ to the Amstel.
The Nieuwezijds Voorburgwal no longer had a defensive purpose.

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