French Morocco had from 1912 to 1935 one of the largest 600 mm (1 ft 11+5⁄8 in) gauge network in Africa with a total length of more than 1,700 kilometres (1,100 mi). After the treaty of Algeciras where the representatives of Great Powers agreed not to build any 1,435 mm (4 ft 8+1⁄2 in) standard-gauge railway in Morocco until the standard-gauge Tangier–Fes railway being completed, the French begun to build military 600 mm (1 ft 11+5⁄8 in) gauge lines in their part of Morocco French Morocco.