Shōnan Monorail Enoshima Line

The line was conceived in the 1960s, a period when several monorail systems were being trialled across Japan as a possible replacement for street trams. It was built as a demonstration line for the suspended-monorail technology of Mitsubishi Heavy Industries, which was competing against the straddle-beam design championed by Hitachi. The project drew on data gathered from the Higashiyama Park Monorail, a short suspended test line that ran inside the Higashiyama Zoo and Botanical Gardens in Nagoya from 1964, and the route between Ōfuna and the resort area of Enoshima was deliberately chosen for its steep gradients and tight curves so as to show off the suspended system's capabilities against the straddle-beam alternative.

Construction drew on the combined resources of the Mitsubishi Group: the track girders and support towers were produced at the Yokohama Shipyard, the rolling stock at the Mihara Machinery Works, the substations by Mitsubishi Electric, and overall coordination was handled by Mitsubishi Estate. The monorail was built above the former Keihin Kyūkō toll road — a private automobile-only road created on land originally acquired for a conventional railway that was never built — which at the time was owned and operated by Keihin Kyūkō and has since been sold to the cities of Kamakura and Fujisawa and turned into an ordinary municipal road.

The Shōnan Monorail company applied for a construction licence on 6 October 1965, and on 26 October 1965 the Transport Council advised the Minister of Transport that granting it was appropriate. The first section, between Ōfuna and Nishi-Kamakura, opened on 7 March 1970, worked by two-car 300-series trains, and the extension from Nishi-Kamakura on to Shōnan-Enoshima opened on 1 July 1971, completing the line. Because the road it follows includes a section with grades as steep as 88‰ and curves as tight as a 25-metre radius, the monorail's own alignment was eased to a maximum gradient of 74.0‰ and minimum curve radii of 100 metres on the main line and 50 metres within stations, with two tunnels carrying the route away from the road.

As lineside development progressed, the monorail took on an increasingly commuter character. Districts around the intermediate stations were redeveloped for light industry, commerce and housing, and former villa areas between Nishi-Kamakura and Mejiroyamashita were rebuilt as residential subdivisions. The two-car trains used at opening could no longer cope with demand, and three-car 300-series trains entered service on 30 January 1975. The line also serves as one route to the resort and tourist areas of Katase Beach and Enoshima, but whereas in 1978 tourism made up about 30 per cent of traffic against 70 per cent for commuting, in recent decades commuting has grown to about 90 per cent. The fleet was modernised over the following decades, with 400-series trains entering service in 1980 and the line's first air-conditioned trains, the 500 series, in 1988.

The line has seen several accidents involving the work vehicles used on the road below. On 20 February 1990 a train bound for Shōnan-Enoshima struck the arm of a crane that was working on the municipal road beneath the track between Nishi-Kamakura and Kataseyama, smashing the front of the car and seriously injuring the driver, though no passengers were killed; service resumed the same afternoon. On 24 February 2008 a train overran Nishi-Kamakura Station because of a brake malfunction, with no injuries, and a later report by the Japan Transport Safety Board attributed the incident to a fault in the control equipment; on 7 November 2008 a train collided with the gondola of an aerial work platform between Shōnan-Fukasawa and Nishi-Kamakura, again without injuries.

Since 2004 the line has been operated by a fleet of seven three-car, aluminium-bodied 5000-series trainsets, which use a variable-voltage variable-frequency (VVVF) drive. The 5000 series entered service on 24 June 2004, the 400 series was withdrawn in July 2004, and the last 500-series train ran on 26 June 2016, shortly after the line carried out its first timetable revision in 23 years on 1 June 2016. In May 2015 majority ownership passed from the Mitsubishi Group to Michinori Holdings. On 1 April 2018 the line began accepting PASMO and other nationwide IC fare cards, and on 13 September 2018 it concluded a sister-monorail agreement with the Wuppertal Schwebebahn in Germany, another suspended monorail and tourist attraction.

• 19656 October: Shōnan Monorail applies for a licence to build a suspended local railway between Ōfuna and Katase; on 26 October the Transport Council advises the Minister of Transport that the licence should be granted.
• 19707 March: the first section, Ōfuna–Nishi-Kamakura, opens — the first suspended monorail in Japan — worked by two-car 300-series trains.
• 19711 July: the Nishi-Kamakura–Shōnan-Enoshima extension opens, completing the 6.6 km line.
• 197530 January: three-car 300-series trains enter service to cope with growing ridership.
• 19803 March: 400-series trains enter service.
• 198831 March: 500-series trains, the line's first air-conditioned cars, enter service.
• 199020 February: a Shōnan-Enoshima-bound train strikes the arm of a crane working on the road below near Kataseyama, smashing the car's front and seriously injuring the driver; no passengers are killed and service resumes that afternoon.
• 199211 July: a timetable revision sets the weekday midday service interval at 7.5 minutes.
• 200424 June: seven-strong, three-car 5000-series trains begin operating; the 400 series is withdrawn in July 2004.
• 200824 February: a train overruns Nishi-Kamakura Station after a brake malfunction, without injuries; a 7 November collision with an aerial work platform between Shōnan-Fukasawa and Nishi-Kamakura also causes no injuries.
• 200926 June: the Japan Transport Safety Board publishes its report on the February 2008 overrun, attributing it to a fault in the control equipment.
• 2015May: majority ownership of the Shōnan Monorail passes from the Mitsubishi Group to Michinori Holdings.
• 20161 June: the line carries out its first timetable revision in 23 years, merging the Saturday timetable into the holiday timetable; the last 500-series train runs on 26 June.
• 20181 April: the line begins accepting PASMO and other nationwide IC fare cards; on 13 September it signs a sister-monorail agreement with Germany's Wuppertal Schwebebahn.