Holzturm

The Wood Tower (German: Holzturm) is a mediaeval tower in Mainz, Germany, with the Iron Tower and the Alexander Tower one of three remaining towers from the city walls. Its current Gothic appearance dates to the early 15th century. It is so named because wood used to be piled next to it on the bank of the Rhine.

Like the Iron Tower, the Wood Tower was used as a watchtower and gate-tower and later as a gaol. It was badly damaged in World War II and accurately reconstructed in 1961 for the two-thousandth anniversary of the city. It currently houses various organisations and clubs.

Beginning in late Roman times, the city of Mainz (then Mogontiacum) was defended by a wall with watchtowers and city gates. The first wall was built shortly before the destruction of the limes in 259/260 CE. Not long after 350, in the course of the abandonment of the Roman camp, this wall was lowered and rubble (spolia) from earlier construction used to enlarge and strengthen it. After the Romans withdrew, it was improved at various times, particularly in the Merovingian and Carolingian periods, becoming what archaeologists studying the city have called the "Roman-Carolingian" wall.

However, in 1160 the continuity of the city's defences was drastically interrupted. There was a longstanding dispute between the citizens of Mainz and their archbishop, Arnold of Selenhofen (and also with the Holy Roman Emperor Frederick Barbarossa); after the archbishop was murdered, the emperor imposed an imperial ban on the city. The city walls and towers were razed (although it is possible that on the inland side the destruction was only partial).

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