Since July 1991, the Prënzebierg nature reserve has had a geological circuit called Circuit Giele Botter. This geological trail has recently been redesigned and the information panels have been updated. Signposted as “GB1”, it is now possible to get an overview of the geology of the former open-cast mining area. The official inauguration of the new trail took place in the presence of representatives of the City of Differdange, the National Museum of Natural History, the Minett Park Fond-de-Gras, the Minett UNESCO Biosphere and the Luxembourg UNESCO Commission.

It was the first geological circuit in Luxembourg and was followed by other geological circuits such as the one in the Pétrusse valley in Luxembourg city, “Mir ginn op d’Grouf” in Stolzemburg or the cross-border circuit “Geologischer Lehrpfad Machtum-Nittel-Wellen”. The route of the Giele Botter tour, which is about 3 km long, follows the disused quarry faces of the former open-cast mine.

© Minett UNESCO Biosphere

Patrick Michaely, Director of the National Museum of Natural History, underlined the importance of science education for his museum and stressed that such educational trails allow visitors to the “Giele Botter” to learn about the region and its geology on site. According to Michaely, this type of knowledge transfer complements what the museum has to offer within its own four walls.

Created in 1991 by the museum’s staff and revised in 2022 by Robert Weis, a palaeontologist at the ‘naturmusée’, the ‘Giele Botter’ geological trail is almost three kilometres long. The starting point is either the Tëtelbierg car park or the water reservoir in Niederkorn. Ten different information boards along the trail provide clear information on the formation of the minette, its extraction and its geological characteristics.

The first mining concession in the Prënzebierg dates back to 1870, and in the 1930s there was intensive tunnel mining at the Giele Botter. Open-cast mining only began after the Second World War and was discontinued in 1977 due to the more ferrous and at the same time cheaper rocks from abroad. Since 20 November 1991, 255 hectares of the Prënzebierg have been classified as a national nature reserve and are also part of the European Natura 2000 network. Since October 2020, the site is one of the core zones of the Minett UNESCO Biosphere.