During the final decades of the
Russian Empire the port city of Baku became a large metropolis due to the discovery of oil in the
Caspian Sea. By the 1930s, it was the capital of the
Azerbaijani SSR and the largest city in Soviet
Transcaucasia. The first plans for a rapid-transit system date to the 1930s, with the adoption of a new general plan for city development. After World War II, the population passed the one million mark, a requirement of Soviet law for construction of a metro system. In 1947, the
Soviet Cabinet of Ministers issued a decree authorizing its construction, which began in 1951. On November 6, 1967, Baku Metro became the Soviet Union's fifth rapid-transit system when the first of track and a depot were inaugurated, in honor of the fiftieth anniversary of the
October Revolution. Due to the city's unique landscape, Baku Metro did not have the typical Soviet "triangle" layout of development, and instead had two elliptical lines which crossed each other in the center of the city at the
Baku railway station. Thus, one line would begin at the southwestern end of the city, and cross on a northeastern axis to follow the residential districts on the northern edge of the city and then snake along to the southeastern and ultimately southern end. This was inaugurated in three stages: Ulduz (1970) and Neftçilər (1972), followed by Ahmedli (1989) and finally Hazi Aslanov (2002), completing the first line. Additionally, in 1970 a branch was opened to a station built in a depot, Bakmil. The second line was to parallel the Caspian coast from Hazi Aslanov through Baku's industrial districts, meeting the first line again at the Baku Railway Terminal, and then continuing westwards before turning north to join Baku's northwestern districts. To accelerate construction, a branch was opened from May 28 station to Khatai in 1968, and in 1976 in the opposite direction towards Nizami. The second and first line used the same station (May 28). This posed no serious problems initially, as the line was two stations long, but when the second stage opened in 1985, lengthening the line to 8 stations (Memar Ajemi), construction of a transfer was desperately needed. In 1993, the first stage of the transfer station Jafar Jabbarli came in operation, but the
end of the Soviet Union, political unrest, the
First Nagorno-Karabakh War and the financial collapse which followed effectively paralyzed any construction attempts in Baku. Furthermore, during the mid-1990s, three
mass casualty incidents took place: on March 19 and July 3, 1994,
terrorist attacks killed 27 people and injured another 91, and on October 28 of the following year a
fire in a crowded train killed 289 and injured 265 others, the world's deadliest subway disaster. In the late 1990s, construction restarted. The first project was the completion of Hazi Aslanov station, partly sponsored by the
European Union. In the mid-2000s, construction of the northern end of the second line, abandoned since 1994, was restarted with Nasimi station opening on October 9, 2008. ==Network==