At the Carrière de Cerin, you can trace how an ancient lagoon and its later use as a quarry became two chapters in the same local history. Fossils and an interpretive trail reveal this unique connection between natural history and human activity.
From Lagoon to Quarry
The Carrière de Cerin is located in Marchamp and is part of the Espace naturel Sensible “Carrière, tourbière et combe de Cerin à Ambléon”. In the 19th century, the quarry was worked for its lithographic limestone. Fossils from the quarry helped demonstrate that a tropical lagoon existed here around 145 million years ago. Geological history and industrial use thus form a single story: the lagoon belongs to a distant past, while the limestone quarrying is part of the site’s more recent history. Those interested in paleontology and heritage will find both in a tangible context here.
A Trail Through the Site’s Development
The “Sur les traces des carriers” trail uses interactive panels and reading tables to guide visitors through the site’s evolution, from lagoon to quarry. The themes form a connected sequence: natural history is followed by the use of limestone. The trail is about 2 kilometres long and takes roughly one hour; terrain conditions may vary. The trail starts at the museum in the hamlet of Cerin, in the commune of Marchamp; visitors can park there. Check local access information again before travelling.
Museum and Fossils
The Musée Paléoécologique de Cerin-Marchamp complements the trail with the results of excavations. It presents findings from excavations renowned worldwide, including fossils of exceptional quality. The museum therefore has a different focus from the trail: the trail tells the story of the site’s development, while the museum showcases the excavation findings. If you are especially interested in the finds, you can consider these two perspectives side by side. The museum is independently accessible to wheelchair users.
Tourbière de Cerin: Observe Nature, Respect the No-Entry Rule
The Tourbière de Cerin is home to numerous remarkable animal and plant species, including several protected species. Entry to the peat bog is prohibited. At the L'oeil de la tourbière viewpoint, there is an orientation panel and explanatory information. At L'oeil de la tourbière, the water forms a circular hollow 40 metres in diameter and 2.5 to 3.2 metres deep. These measurements help convey the scale of this natural feature; the panel provides orientation and explanations on site. The key point for planning your visit is the clear boundary: the peat bog is a habitat, not an area to walk through.
Discover more destinations: Chevillard, Thoissey, Jayat, Chavannes-Sur-Suran, Ars-Sur-Formans, Replonges, Simandre-sur-Suran, Saint-Bois.
For the broader travel overview: Ain.
