Keikyū Airport Line

On 28 June 1902 the Keihin Railway (Keihin Electric Railway) opened the line — then called the Anamori Line — from Kamata, the present-day Keikyū Kamata, to Anamori Station, which stood near the present site of Tenkūbashi Station. It was built on standard gauge (1,435 mm) and electrified at 600 V DC. The line's original purpose was to carry pilgrims to the Anamori Inari Shrine, which then stood on land that is now within the airport. To build ridership, the Keihin Railway developed leisure attractions in the surrounding area, including a baseball park, tennis courts, a swimming pool and an amusement park. The Anamori Line opened before the company extended toward Shinagawa, a sequencing driven by the commercial success of pilgrimage traffic to Kawasaki Daishi.

The line's gauge was changed twice. In 1904 it was regauged to 1,372 mm in conjunction with the Keikyu Main Line, and the entire route was double-tracked by 1910. It was later converted back to standard gauge (1,435 mm) in 1933, and the overhead supply was raised from 600 V to 1,500 V DC in 1947. In 1931 Haneda Airport opened roughly 500 m north of Anamori Station, and the line gradually took on airport-passenger traffic alongside its shrine-pilgrimage role.

The Anamori Line was the primary rail route to Haneda Airport until 1945, when the airport was taken over by the United States Armed Forces at the end of the Second World War. The shrine and local residents were forcibly evicted, and the line was reduced to single track to accommodate a parallel freight line. For decades afterward the route terminated on the far bank of the Ebitori River, across from the airport, and functioned mainly as a local branch for shrine visitors and residents rather than as airport access. The corporate ownership also shifted in this era: the Keihin Electric Railway was absorbed into Tokyo Kyuko Electric Railway (the wartime "Greater Tokyu") in 1942, and the present Keihin Kyuko (Keikyu) was separated out again in 1948. On 1 November 1963 the route was renamed the Airport Line. Even so, it was not widely used for airport access, owing to limited service frequency and the absence of through services to central Tokyo — particularly after the Tokyo Monorail opened in 1964 and provided direct service from Hamamatsuchō to the airport terminal.

Rail service onto the airport island resumed in April 1993, when the line was extended across the river to a new Haneda Airport Station at the present-day site of Tenkūbashi Station; that year Haneda Airport underwent significant expansion, and Keikyu received government approval to serve the facility after the monorail was judged to have insufficient capacity. On 18 November 1998 the Airport Line was further extended from Tenkūbashi to a new Haneda Airport Station — now Haneda Airport Terminal 1·2 Station — directly connecting the airport terminal building and enabling through services to major stations such as Shinagawa and Yokohama. An infill station serving the international terminal, originally Haneda Airport International Terminal Station and now Haneda Airport Terminal 3 Station, opened on 21 October 2010.

Today the Keikyū Airport Line is double-tracked (with a paired single-track section between Keikyū Kamata and Kōjiya), electrified at 1,500 V DC, and has a maximum speed of 110 km/h. Most trains run through beyond the Airport Line onto the Keikyū Main Line — northbound to Shinagawa in central Tokyo, with some services continuing onto the Toei Asakusa Line, or southbound to Yokohama, with select services continuing as far as Zushi-Hayama. Keikyu operates several service tiers on the line, from all-stations Local trains up to the limited-stop Airport Limited Express, restoring the route to its role as one of the two rail links to Haneda Airport, alongside the Tokyo Monorail.

• 190228 June: the Keihin Railway opens the standard-gauge (1,435 mm) Anamori Line from Kamata to Anamori Station, electrified at 600 V DC, to carry pilgrims to the Anamori Inari Shrine.
• 1904The line is regauged to 1,372 mm in conjunction with the Keikyu Main Line.
• 1910The entire route is double-tracked.
• 1931Haneda Airport opens roughly 500 m north of Anamori Station; the line gradually takes on airport traffic.
• 1933The line is converted back from 1,372 mm to standard gauge (1,435 mm).
• 1942The Keihin Electric Railway is merged into Tokyo Kyuko Electric Railway (the wartime 'Greater Tokyu').
• 1945At the end of WWII the airport is taken over by the United States Armed Forces; the line is cut to single track to accommodate a parallel freight line.
• 194725 December: the overhead supply is raised from 600 V to 1,500 V DC.
• 1948The present Keihin Kyuko (Keikyu) is separated out of Tokyo Kyuko Electric Railway.
• 19631 November: the route is renamed the Airport Line.
• 1993April: rail service onto the airport island resumes; the line is extended across the river to a new Haneda Airport Station at the present-day site of Tenkūbashi Station, with through services to central Tokyo.
• 199818 November: the Airport Line is extended from Tenkūbashi to a new Haneda Airport Station (now Haneda Airport Terminal 1·2 Station), directly connecting the terminal and enabling through services to Shinagawa and Yokohama.
• 201021 October: an infill station serving the international terminal (now Haneda Airport Terminal 3 Station) opens.