City walls of Nuremberg, City walls in Nuremberg, Germany

The city walls of Nuremberg form a complete ring around the old town with dozens of towers, gates, and bastions built in different styles and periods. The fortification includes walkways along the top, protected passages, and sections that show how defensive design changed as military technology advanced.

The first fortifications are assumed to date from the 11th century, and by the 13th century the Sebald and Lorenz settlements on either side of the Pegnitz were each walled separately. In 1320–1325 walls were built across the river to join them. The last circuit was closed in 1400, five kilometres long and shaped as a crooked parallelogram with four massive gate towers. The moat, dug from 1430 in response to the Hussite wars, was on average 12 metres deep and up to 20 metres wide, and was finished in 1452.

Since 1540 the wall towers have carried a seven-colour alphabet of letters and paint: black from Luginsland at the castle east to Schwarz Z on the Schütt island, then blue, red, green back to the castle. Many of these old markings can still be read on the towers today.

The full ring is about five kilometres and takes roughly an hour at a brisk pace; the route is marked by excavations that show the scale of the moat dug from 1430 and finished in 1452. The moat was on average 12 metres deep and up to 20 metres wide, and never held water. Seven gates gave access on land: the old Tiergärtnertor, the four later gate towers (Laufer Tor, Frauentor, Spittlertor, Neutor) and two pedestrian passages, the Hallertürlein and the Wöhrder Türlein.

In 1540 the towers were labelled with a seven-colour alphabet: the black section runs from the castle (Luginsland, Schwarz A) east to the island Schütt (Schwarz Z), then blue, red, green follow round to Grün O at the castle again. Many of these old letters and colours can still be read on the towers today.