Narita Sky Access Line

Unusually, the line is run under a vertical-separation arrangement: Keisei Electric Railway is the Category-2 operating carrier over the whole route, paying track-access fees to four infrastructure-owning companies. Hokusō Railway owns the Keisei-Takasago–Komuro section, Chiba New Town Railway the Komuro–Imba-Nihon-idai section, Narita Rapid Rail Access the section on to the junction with the Narita Airport Rapid Railway, and Narita Airport Rapid Railway the final stretch into the airport. The 32.3-kilometre Keisei-Takasago–Imba-Nihon-idai portion is physically the existing Hokusō Line, shared between the two operators, and the section into the airport overlaps part of the Keisei Main Line. The line carries two of its own service types — the reserved-seat Skyliner limited express and the fare-only Access Express commuter trains — and through-running trains continue beyond Keisei-Takasago toward central Tokyo, the Toei Asakusa Line, the Keikyū network and Haneda Airport.

The line’s origins lie in a 1982 study. On 31 May that year an investigative committee on high-speed rail access to the New Tokyo International Airport submitted three options to the Ministry of Transport: Plan A, rebuilding the route of the cancelled Narita Shinkansen project; Plan B, extending the Hokusō Line eastward from the Tokyo side via Takasago and Komuro to the airport; and Plan C, branching off the existing Narita Line to reach the airport directly. On 1 November 1984 the Ministry announced it would promote the Plan B route, and on 11 July 1985 the scheme was written into Transport Policy Council Report No. 7. Plan C was realised first, however: it opened in 1991 as the Narita Line airport branch and the Keisei Main Line spur, becoming the route of the JR “Narita Express,” while Plan B languished.

Progress on Plan B resumed at the end of the 1990s. A business-promotion study committee for the “Narita New Rapid Railway” was set up on 23 March 1999, and on 27 January 2000 Transport Policy Council Report No. 18 listed the line as one that should appropriately open by 2015. The infrastructure-owning company, Narita Rapid Rail Access Co., Ltd., was established on 25 April 2002, and railway-business permits for it (Category 3) and for Keisei (Category 2) were granted on 5 July 2002. The Minister of Land, Infrastructure, Transport and Tourism authorised construction of the new line on 21 December 2005, and a groundbreaking ceremony was held in Narita on 4 February 2006.

Construction combined upgrading existing track with building an entirely new line. The 32.3 kilometres of the Hokusō Line between Keisei-Takasago and Imba-Nihon-idai were refurbished for higher-speed running, while a new double-track section of about 19.1 kilometres was built east from Imba-Nihon-idai to the airport, partly along disused viaducts and rights-of-way that had originally been prepared for the abandoned Narita Shinkansen. The new section crosses the Imba-numa wetlands by bridge; environmental concerns over this bird-rich area led to reviews and protective measures during planning. A single intermediate station on the new section was named “Narita Yukawa” through a public contest on 28 April 2009, and on 16 December 2009 Keisei disclosed the line’s formal name, the chosen “Narita Sky Access” nickname, the limited-express stopping pattern and the approved fares. The total project cost was about ¥126.1 billion.

The line was completed in March 2010, and after roughly four months of crew familiarisation running that began on 25 March 2010, it opened to traffic on 17 July 2010, when Skyliner services started over the new route. Because the new alignment is far more direct than the older Keisei Main Line approach, the fastest Nippori–Airport Terminal 2 journey fell from 51 minutes to 36 minutes, a saving of fifteen minutes. The 160 km/h maximum speed between Imba-Nihon-idai and Airport Terminal 2 is achieved over specially equipped track, including a roughly 135-metre swing-nose turnout at Narita Yukawa, and a dedicated high-speed “GG” signal aspect shown only to the Skyliner; from the 2015 withdrawal of the Hokuetsu Express “Hakutaka” this became the only regularly operated 160 km/h running in Japan.

In the years after opening the line saw a series of timetable refinements. The Great East Japan Earthquake of 11 March 2011 suspended through-running with the Toei Asakusa and Keikyū lines and halted the Skyliner, with services restored over the following days. From the timetable revision of 26 February 2022, Toei 5500 series trains began working Access Express services on the line, and from 26 November 2022 certain Aoto-stopping Skyliner trains were given an additional stop at Shin-Kamagaya to improve access to the Kashiwa and Matsudo areas of Chiba Prefecture. Today the line is the principal fast rail link between central Tokyo and Narita Airport, complementing the slower Keisei Main Line and JR’s Narita Express.

• 198231 May: an investigative committee on high-speed rail access to the New Tokyo International Airport submits three route options (A/B/C) to the Ministry of Transport.
• 19841 November: the Ministry of Transport announces it will promote the Plan B route, extending the Hokusō Line eastward to Narita Airport.
• 198511 July: the scheme is positioned in Transport Policy Council Report No. 7.
• 199923 March: the 'Narita New Rapid Railway' business-promotion study committee is established.
• 200027 January: Transport Policy Council Report No. 18 lists the line as one that should appropriately open by 2015.
• 200225 April: the infrastructure-owning company Narita Rapid Rail Access Co., Ltd. is established; on 5 July railway-business permits are granted to it (Category 3) and to Keisei (Category 2).
• 200521 December: the Minister of Land, Infrastructure, Transport and Tourism authorises construction of the new Narita Rapid Railway Access line.
• 20064 February: a groundbreaking ceremony is held in Narita; construction of the new line and upgrading of existing track begin.
• 200928 April: the new intermediate station is named 'Narita Yukawa' by public contest; on 16 December Keisei discloses the line's formal name, the 'Narita Sky Access' nickname, the stopping pattern and the fares.
• 201017 July: the line opens after about four months of crew familiarisation running (from 25 March); Skyliner services start at up to 160 km/h, cutting the fastest Nippori–Airport Terminal 2 time from 51 to 36 minutes. Total cost ~¥126.1 billion.
• 201111 March: the Great East Japan Earthquake suspends through-running with the Toei Asakusa and Keikyū lines and halts the Skyliner; services are restored over the following days.
• 202226 February: Toei 5500 series trains begin operating Access Express services on the line.
• 202226 November: Shin-Kamagaya Station is added as a stop for certain Aoto-stopping Skyliner trains, improving access to the Kashiwa and Matsudo areas.