The story
Keisei was founded on June 30, 1909 and began services on November 3, 1912, initially operating local train service in eastern Tokyo. Its main line reached Narita in 1930 and Ueno in 1933.
Originally a narrow gauge (1,372 mm or 4 ft 6 in Scotch gauge) operator, Keisei converted to 1,435 mm (4 ft 8+1⁄2 in) standard gauge in 1959. In 1960, Keisei began through service with the Toei Asakusa Line, the first interline through service arrangement in Japan.
Skyliner service began in 1973 and started serving the airport in 1978, when the first Narita Airport Station opened (today's Higashi-Narita station).
A new underground station was opened in 1991 to provide a more direct connection to terminal 1, and in 1992 service began to terminal 2.
On July 17, 2010, Skyliner switched its route to the newly built Narita Sky Access and reduced the travel time by 15 minutes.
On 31 October 2023, Keisei announced plans to acquire its subsidiary Shin-Keisei Electric Railway. The acquisition was completed on 1 April 2025, and the Shin-Keisei Line was renamed to the Matsudo Line. The acquisition added 26.5 km (16.5 mi) of trackage to the railway's operations.
From Wikipedia’s article on Keisei Electric Railway, shared under CC BY-SA 4.0.4