Originally a Viking fishing village established in the 10th century in the vicinity of what is now Gammel Strand, Copenhagen became the capital of Denmark in the early 15th century. Beginning in the 17th century it consolidated its position as a regional centre of power with its institutions, defences and armed forces. After a plague outbreak and fire in the 18th century, the city underwent a period of redevelopment. This included construction of the prestigious district of Frederiksstaden and founding of such cultural institutions as the Royal Theatre and the Royal Academy of Fine Arts. After further disasters in the early 19th century when Horatio Nelson attacked the Dano-Norwegian fleet and bombarded the city, rebuilding during the Danish Golden Age brought a Neoclassical look to Copenhagen's architecture. Later, following the Second World War, the Finger Plan fostered the development of housing and businesses along the five urban railway routes stretching out from the city centre.
The Copenhagen Metro launched in 2002 serves central Copenhagen. The Copenhagen Metro is scheduled to expand radically with the opening of the City-ring line during fall 2019, the new line will connect all inner boroughs of the city by metro, including The Central Station, and will open up 17 new stations for Copenhageners. The new metro line is a part of the city's strategy to transform mobility towards sustainable modes of transport such as public transport and cycling as opposed to automobility. Additionally the Copenhagen S-train, the Lokaltog (private railway) and the Coast Line network serves and connects central Copenhagen to outlying boroughs. The Copenhagen-Ringsted Line will relieve traffic congestion in the corridor between Roskilde and Copenhagen.
Copenhagen's name reflects its origin as a harbour and a place of commerce. The original designation in Old Norse, from which Danish descends, was Kaupmannahǫfn [ˡkaupmanːahɒvn] (cf. modern Icelandic: Kaupmannahöfn [ˡkʰøyhpmanːahœpn], FaroeseKeypmannahavn), meaning "merchants' harbour". By the time Old Danish was spoken, the capital was called Køpmannæhafn, with the current name deriving from centuries of subsequent regular sound change. An exact English equivalent would be "chapman's haven". However, the English term for the city was adapted from its Low German name, Kopenhagen.
(English chapman, German Kaufmann, Dutch koopman, Swedish köpman, Danish købmand, Icelandic kaupmaður: in all these words, the first syllable comes ultimately from Latin caupo, "tradesman".) Copenhagen's Swedish name is Köpenhamn, a direct translation of the mutually intelligible Danish name.