Metro Line M4 (Budapest Metro) Metro Line M4 (Budapest Metro) Line 4 (officially: South Buda–Rákospalota (DBR) Line, Metro 4 or M4, and unofficially: Green Line), is the fourth line of the Budapest Metro. It opened on 28 March 2014. The first section, 7.4 km in length and consisting of ten stations, connects the southwestern Kelenföld vasútállomás located in Buda, and the eastern Keleti pályaudvar in Pest, under the River Danube. While three additional sections — one an eastern extension to Bosnyák tér, the second west to Virágpiac, and a third further east to Újpalota — have been planned, these remain unfunded by the Budapest city
Budapest Frigyes Feszl (1821–1884). Another noteworthy structure is the Budapest Western Railway Station, which was designed by August de Serres and built by the Eiffel Company of Paris in 1877. Art Nouveau came into fashion in Budapest by the exhibitions which were held in and around 1896 and organised in connection with the Hungarian Millennium celebrations. Art Nouveau in Hungary ("Szecesszió" in Hungarian) is a blend of several architectural styles, with a focus on Hungary's specialities. One of the leading Art Nouveau architects, Ödön Lechner (1845–1914), was inspired by Indian and Syrian architecture as well as traditional Hungarian decorative designs. One