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The tower mill on the city wall in Kempen.
The Narren-mill in Viersen-Dülken
'The Narren-mill is a post mill with sail-gate sails and – as a rarity – with brick-walled trestle in Viersen's village Dülken.
On the 11. November every year the members of the Narrenakademie (fools' academy, in the past mainly academics, merchants and aldermen) line up on their wooden hobby-horse for the fools' ride around the windmill and opened thus the Dülken carnival season. The ride around the Narren-mill can be traced back as tradition into the 18th-century. But was probably the practice of the mounted academy right from the start. Old medals, flags, hats and books, which prove this are being kept in the mill museum.'
Source: Wikipedia
The post mill in Tönisberg