The Maizuru-sen is an electric (DC 1500 V) line leading to two inlets at the southern rim of Wakasa Bay. The two inlets are separated by a hill about 300 m high, on the western side is the old castle town of Maizuru (with Nishi Maizuru – West Maizuru – station), on the eastern side the area developed around dockyards and one of Japan's most important naval bases (with Higashi Maizuru – East Maizuru - station). The Maizuru-sen branches off the San'in Honsen at Ayabe and is 26, 4 km long.
At Higashi Maizuru the line is linked to the Obama-sen, which continues along Wakasa Bay to Tsuruga and the Hokuriku Honsen. Passengers change at the new high-level platform (built 1996) to the electric class 125 trains for Tsuruga.
The Maizuru-sen, built in 1904, formed part of the direct access from the Ôsaka area to the Japan Sea and had great strategic importance. In 1907 it became state owned.
Three freight lines serving the port area of Maizuru closed between 1941 and 1985, freight services on the Maizuru-sen itself ended in 1999, the year of electrification.
There is a fairly regular local service between Higashi Maizuru, Ayabe and Fukuchiyama (on the San'in Honsen), and an express service to Kyôto (and vice versa) about every two hours. Two express trains a day are operated by diesel sets of the Kyôto Tango Tetsudô (KTR), the others are JR trains. The Maizuru portion of the express trains are coupled to the coaches coming from Ama no Hashidate or Kinosaki Onsen at Ayabe; the KTR trains from the direction of Ama no Hashidate originate at Toyooka and come via Kumihama, Ama no Hashidate, Miyazu and Fukuchiyama.
