Ouvrage Arrondaz is a lesser work (petit ouvrage) of the Maginot Line's Alpine extension, the Alpine Line, also known as the Little Maginot Line. The ouvrage consists of one entry block, one infantry block, and one observation block fin the vicinity of the Col de Fréjus to the south of Modane at an altitude of 2,500 metres (8,200 ft). All but one of the blocks are presently buried by later construction.