It is actually a continuous ditch that has been dug in the east of the town centre and is divided by a stone bridge.
At the time of the founding of the city, these moats were protecting the young city and its inhabitants from enemies. The "Walchergraben" was named after the "Tuchwalker", who were situated there. In the last century, a "Schleifmühle" (mill) was constructed there, and so it was renamed "Schleifmühlgraben".
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