Since the 15th century, the local gemstone deposits have been processed in so-called grinding mills. Of these, 183 stood on the Idarbach, the Nahe and other streams around Idar-Oberstein. There were 56 loops on the Idarbach alone. In the first three decades of the 20th century, the stream loops were shut down one after the other. They disintegrated and disappeared from the landscape after a short time.

The Historical "Weiherschleife" Grinding - actually known as the "Kallwies-weiherscheife" - remained in operation until 1945. It then threatened to disinte-grate, but was restored in 1953/54. It is the last agate grinding mill driven by a waterwheel on the Idarbach. The expert tour guides demonstrate the pro-cessing methods of earlier centuries live to the visitors on the large sandstone grinding wheels.

New in the Historical "Weiherschleife" Grinding is a multimedia show with the motto "The Secret of the Precious Stones". Spectacular, modern and infor-mative. The exhibition was supplemented by a mineral room, which particularly covers the esoteric area. The explanations in the "Historical Weiherschleife" ", in the small exhibition and in the multimedia show, can be performed in 6 languages, German-English-French-Danish-Polish and Dutch.

On the pond, the so-called "Kallwiesweiher", which serves as a water reservoir for operating the large water wheel of the pond loop, there are 3 pedal boats that can be rented for a modest fee. - a special pleasure for young and old.

Advance registration for groups of 20 or more is necessary (>>> Follow the link for registration). The management of the pond loop will be happy to provide you with further information.