Schiefergrube Herrenberg

Useful Information

Location:	Bundenbach. (49.8490464, 7.3887194)
Open:	closed. Fossilienmuseum: Easter to OCT Mon 14-16, Tue-Thu 11-16, Fri-Sun 10-17. [2026]
Fee:	closed. Fossilienmuseum: Adults EUR 3, Children (5-17) EUR 1,50. Groups (10+): Adults EUR 2,50, Children (5-17) EUR 1. [2026]
Classification:	Slate Mine
Light:	Electric Light
Dimension:
Guided tours:
Photography:
Accessibility:
Bibliography:
Address:	Grube Herrenberg, Ortsgemeinde Bundenbach, 55626 Bundenbach, Tel: +49-6544-9272. E-mail:
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then. Please check rates and details directly with the companies in question if you need more recent info.

History

1519	oldest lease for a slate quarry.
1822	slate mine Herrenberg first mentioned.
1865	21 slate mines in the Bundenbacher area.
1964	slate mine Herrenberg closed.
1975	development as a show mine.
1976	show mine opened to the public.
1988	made accessible to wheelchair users.
2000	last working slate mine of Bundenbach closed.
2022	Show mine closed.

Geology

The slate of Bundenbach is of sedimentary origin. In a deep sea continually small amounts of clay were sedimented from the water, forming thin and dark layers of very small grain size. It was deposited about 390 million years ago, during the early Devonian. It contains few but extraordinary fossils, which were collected by the slate workers.

The specialty of the Bundenbach fossils is the extremely good preservation, even of fine deatails and soft parts of the bodies. This is a result of the fine silt the animals were embedded in and the anaerobic (oxygene less) chemistry, which reduced decomposition. The decomposition also changes the chemical balance and so pyrite from the pore water was deposited in the animals, preserving them very well.

Most important are the trilobites (Phacopidae, Chotecops ferdinandi) and arthropods with preserved soft tissue (Nahecaris steurtzi).

Description

The slate of Bundenbach may be used for various purposes and was mined for centuries. The first written account is a slate mine lease of the Herren von Wiltberg with the two Bundenbach inhabitants Peter and Niklas Huppen. They leased the ground for four years. But the slate mining continued and became more and more important. The heyday of slate mining was during the 19th century, in the year 1865 21 slate mine existed in the Bundenbach area. But during the 20th century, with increasing wages, the mining was not rentable any more. Since the last quarry was closed in 2000 only foreign slate is processed.

In the Grube Herrenberg (Herrenberg mine) the underground mining of slate is explained. The show mine was developed by citizens of Bundenbach in a private initiative. Later, it was operated by the municipality of Bundenbach with the help of experienced miners. However, the show mine was closed indefinitely in 2022 after a rockfall. Apparently, costly safety measures are necessary, but there is no money for them. The slate is not very stable, and there are also construction defects caused by the volunteers. The community applied for funding in 2024 but did not receive it, so the show mine is likely to remain closed permanently.

A few years ago, the show mine was expanded to include a fossil museum, where countless fossil finds are on display. This is still open and definitely worth a visit.