The Fréjus Rail Tunnel is a rail tunnel of 13.7 km length in the European Alps, carrying the Turin–Modane railway through Mont Cenis to an end-on connection with the Culoz–Modane railway and linking B

Ouvrage Saint-Gobain is a work of the Maginot Line's Alpine extension, the Alpine Line. The ouvrage consists of one entry block, one infantry block, one artillery block, one observation block and one