From 3 to 6 October 2026, Luxembourg will once again take part in the UNESCO Geodiversity Days, an international initiative celebrating geological diversity and raising awareness of its importance for society and nature. A variety of guided walks, excursions and events will take place across Luxembourg and neighbouring regions.

Micheville: Discovering the story of the Minette

On Saturday, 3 October, the Minett UNESCO Biosphere will host a guided tour entitled“The Minette of Lorraine and Luxembourg: a geological treasure across the border.” The excursion will lead visitors through the former open-pit mine of Micheville in Villerupt, one of the most important geological and industrial heritage sites in the region.

For decades, Micheville was a major iron ore extraction site. Since mining activities ended in 1974, the 463-hectare area has gradually been transformed into a protected natural landscape. Participants will learn about the geological origins of the Minette ironstone, the industrial history of the site and the remarkable return of biodiversity over the past fifty years. The tour will be led in the presence of the authors of the book The Minette of Lorraine and Luxembourg – A Geological Treasure Across the Border.

Sign up here to participate in this free workshop.

Geological experiences across the region

The programme begins on 3 October in Haut-Martelange with“Three Slate Quarries – Three Destinies”, a guided walk exploring how former slate mining sites are being preserved, studied and reused for innovative projects.

On 4 October, visitors can join Urban Fossils in Luxembourg City, a fascinating exploration of fossils hidden in the natural stones used throughout the urban landscape. Later that day, the Natur- & Geopark Mëllerdall will lead a hike through the Héikraiz near Heffingen, showcasing geological, landscape and human history spanning millions of years.

The celebrations conclude on 6 October with a public conference on critical raw materials, focusing on the role of geological resources in Europe’s energy transition and the challenges of future resource supply.

Understanding the ground beneath our feet

The UNESCO Geodiversity Days invite everyone to discover how geology shapes landscapes, biodiversity and cultural heritage. Whether visiting Micheville, Martelange, Luxembourg City or Heffingen, participants will gain new insight into the natural history that lies beneath our feet.

Read the press release for the UNESCO Geodiversity Days 2026.

Find here all the deatils about the activities organised this year.