伊豆箱根鉄道
In 1949, the Japan National Railways began semi-express and limited-express train operations from Tokyo. The Sunzu Railway Company was acquired by the Izuhakone Railway on June 1, 1957. The line was upgraded from 600 V to 1,500 V on September 7, 1959. All freight operations were discontinued as of June 16, 1972. An ATS system was installed in December 1972 and a CTC system in 1985 (upgraded in 2007).