System of fortifications Séré de Rivières (name of a general) in the Authion mountains

The constructions follow more or less the ridge line between Roya river and Vésubie river.

Period Nineteenth

Accessibility No

Visitable Yes

The military constructions of the Authion mountains were built as part of the program of General Séré de Rivières, Chief of Engineering at the French Ministry of War in a context of international tensions that followed the reunion of the County of Nice to France in 1860, then the war of 1870.

In 1877, the French army began to draw mule tracks for the yards. The track coming from Breil through Maglia valley was widened and a nice little tunnel was built between 1887 and 1894.

These works of occupation of the site were intended to prevent an opponent from seizing the massif of Authion. Each redoubt includes internal barracks for combat situations. The non-fortified barracks of Plan Caval and Cabanes Vieilles completed the accommodation in peaceful periods.

Three fortresses were completed between 1887 and 1900, on lForca peaks, Milles Fourches and finally Trois Communes.

During the 1930s, more modern Maginot structures were built in the Authion Massif to adapt the lines of defense to combat modes evolutions.

Conditions of visit

The massif of Authion is accessible by car in summer by the valley of Vésubie. It is also possible to access the massif by hiking trails from Maglia Valley (Breil-sur-Roya).
The barracks of Cabanes Vieilles and Plan Caval are the only one located on the roadside. The others are accessible only to valid people.
Restricted visits (danger inside buildings)


Additional information


  • Raybaud Claude, Fortifications de l’époque moderne dans les Alpes-Maritimes, Éditions Serre (collection L’Ancre solaire), Nice, 1992.
  • Mary Jean-Yves, Hohnadel Alain, Sicard Jacques et Vauviller François, Hommes et ouvrages de la ligne Maginot, éditions Histoire & collections, coll. « L’Encyclopédie de l’Armée française »: Paris. t. 4 : la fortification alpine, 2009, t. 5 : Tous les ouvrages du Sud-Est, victoire dans les Alpes, la Corse, la ligne Mareth, la reconquête, le destin, 2009.

Useful links

1) Site de Plan Caval

3) Site de la Forca

4) Site de Mille Fourches

5) Site de Cabanes Vieilles

6) Pointe des Trois Communes