X3 (train)

The X3 is an electric multiple unit high-speed train used by Arlanda Express on the airport rail link service between Stockholm Central Station and Stockholm Arlanda Airport in Sweden. Alstom built seven of these four-car units at its Washwood Heath plant in England in 1998 and 1999. The X3 is part of the Alstom Coradia family and can reach speeds up to 200 km/h. The trains are painted white with yellow ends and have a Scandinavian designed interior. The units use standard gauge tracks and are fed electricity at 15 kV 16.7 Hz AC like the rest of the Swedish railway network, but the trains use separate stations at Arlanda and dedicated tracks at Stockholm Central, in both cases with platforms higher than at other stations in Sweden, allowing step-free access to the trains without the use of low floors. In 2025 an order for seven six-carriage Stadler Flirts was placed to replace the X3 fleet.