Route des Crêtes

Route des Crêtes (English: Route of the Ridges) is an 89 km (55 mi) road in the Vosges Mountains in eastern France, which passes through the Parc Naturel Régional des Ballons des Vosges. It connects Sainte-Marie-aux-Mines (north) with Cernay (south) and runs on the border of the departements of Haut-Rhin (68) and Vosges (88). Most of the route is at an elevation in excess of 950 m (3,117 ft), with the highest point being at the Col du Grand Ballon (1,343 m (4,406 ft)). The road is generally open from April to November, but most of the route is closed in the winter by snow.

The ridge forms part of the boundary between the Alsace and Lorraine regions of France. In 1871, Alsace was ceded to Germany under the Treaty of Frankfurt, and thus the ridge formed the boundary between France and Germany.

During the First World War, the French military decided to create a road to follow the ridge, thus allowing easier access to the valleys on both sides, enabling the faster movement of French troops. The route was mostly just below the ridge to the west and was thus protected from German gunfire.

From Sainte-Marie-aux-Mines (Haut-Rhin) (elevation 282 m (925 ft)), the Route des Crêtes is accessed via D48 and Col des Bagenelles (903 m (2,963 ft)), which leads to the Col du Bonhomme (949 m (3,114 ft)), on the route connecting Saint-Dié-des-Vosges (west) and Colmar (east).

The route (now D148) continues south via the Col de Louchbach (978 m (3,209 ft)) to the Col de Calvaire (1,134 m (3,720 ft)), where it enters the department of Vosges. The route (now D61) then passes the Gazon du Faing (1,303 m (4,275 ft)) from where there is a panoramic view stretching to the Black Forest across the Rhine valley in Germany and the Hohneck, Petit Ballon and Grand Ballon summits in the Vosges mountains.

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Wikipedia