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Earthquakes, rockslides, mudslides have shaped the city of Saint-Étienne. (©MS / news Saint-Étienne)
Does Saint-Étienne have a link with Rome? Not so much at first glance, apart from its topography and the seven hills that border the two cities.
300 million years ago
The capital of the Loire is located along the valley of the Furan. Surrounded by hills to the east and west, the city has developed taking into account this particular topography.
300 million years ago, during the primary era, at the time of the Carboniferous, the region of Saint-Étienne was located at the heart of a 4000m high mountainformed by the collision of ancient continents.
Le Country of art and history in Auvergne-Rhône-Alpes, explains that “during this period restless (earthquakes, landslides, mudslides, etc.) marshy areas settle in. Leaves, branches and trunks accumulate, forming future coal sites. »
This restless period is determined by 1893 by geologists. For 50 million years, this mountainous area erodes more or less quickly depending on the hardness of the rocks, to reach a minimum altitude of 300 or 400 m.
Six main hills
Today, the city culminates on average at 517 m on average, counting 6 main hills, Mont d’Or and Montaud in the west, Mont Dormand (Vivaraize), Villeboeuf le Haut, Montferré and Crêt-de-Roc in the east which range from 566 to 671 m of altitude.