The evolution of Haut-Martelange's industrial site

For nearly two centuries, slate was extracted and processed in the quarries of Haut-Martelange. That chapter of industrial history is preserved at the 8-hectare Haut-Martelange Slate Museum.

Slate from Luxembourg

From 1790 to 1986, slate was excavated from the Haut-Martelange quarries, where labourers often worked 10-hour days in difficult conditions at depths of up to 168m. According to Marco Schank, president of the "Friends of the Slate" association, the quarry employed roughly 600 people after 1900 and was a vital employer for the northern region. In total, 95,000m³ of slate were extracted from the site, which continued operations even during the Second World War.

Schank noted that many workers contracted silicosis, a lung disease that went unrecognised as an occupational illness for a long time. Slate extraction ended in 1956, and the site closed permanently in 1986.

The first open day was organised by "Friends of the Slate" in the summer of 1992, at a time when there was no formal museum. Doris Thilmany, the museum's director, explained that from the outset, the goal was to preserve the entire site as a coherent historical entity. She emphasised that Haut-Martelange was a self-sufficient industry, complete with an underground mine, industrial buildings, repair workshops, administrative offices, workers' housing in the valley, and the owner's villa on the hill.

Insight for children of all ages

The museum is a popular destination for school classes, which visit throughout the year to learn about historical working conditions 42m underground in the Johanna pit.

Thilmany stated that programmes are tailored to each group but consistently focus on the quarrymen's craft. "For us, the stone is at the heart of it all", she explained. Following a tour, every child has the opportunity to make their own slate tablet to take home. The site also features a historic train on a 600mm gauge track.

The 8-hectare grounds contain approximately 20 buildings preserved from its operational era, including the boss's villa. The Rother family, who owned the quarry, lived on-site from 1900 to 1985. The National Institute for Architectural Heritage (INPA) is currently renovating the villa, which is scheduled to open to the public in June 2026.

Patrick Diederich, an architect with the INPA, described the property as an impressive symbol of its time. "The Rother family only moved here after they had bought up all the small plots of land – after that, they created something grand here", he said.

Diederich explained that industrialists like the Rothers were considered "the new nobility, the modern aristocracy" around 1900. While the family lived – and celebrated – on the site, the workers laboured alongside them.

The renovation has uncovered evidence of the family's wealth, including "extraordinary" floral patterns hidden under layers of flooring. "We were also in contact with our heritage conservation colleagues from Germany, and they have never seen anything like it", Diederich noted.

Slate Museum: Open every day

The Haut-Martelange Slate Museum is open daily from 10am to 6pm, closing only on Mondays and for Christmas and New Year's Eve.

The museum welcomed 23,900 visitors in 2024. For the first six months of this year, it has recorded 10,800 visitors.

Guests have the option to explore the underground mine either with a guide or independently. It should be noted that children must be at least four years old to enter the underground sections. General admission to the museum grounds is free, providing access to all above-ground buildings and exhibits.

For further details visit the official website: www.ardoise.lu.