Line 9 (Beijing Subway)

Line 9's route drawn to scale.

In 1989, the State Council decided to build Beijing West railway station on the Beijing-Kowloon railway. Subway planning had determined that Beijing West railway station would be the interchange between Lines 7 and 9. However, no provision for an interchange station was added in the railway station's design. The railway station was completed in 1996.[2] 15 years later Beijing West Station was rebuilt and expanded with provisions added to the basement of the station for Lines 7 and 9.[3] In 2002, in preparation for the 2008 Beijing Olympics, it was proposed that the first section of Line 9 should be built between Baishiqiao and Beijing West railway station (today's National Library to Beijing West railway station section). The entire length of the proposed line was 5.8 kilometers.[4] However, the line only started construction in April 2007,[5] with a planned opening date of 2010[6] and the original northern section between Baishiqiao to Beijing West Station was further delayed until 2012,[7] making an opening before the Olympics unlikely.

On December 31, 2011 the 11.1 km (6.9 mi), nine-station southern section from Guogongzhuang to Beijing West railway station opened.[8][9] At the time the line was only connected to the Fangshan Line, isolated from the rest of the Beijing Subway network.[10] Passengers had to transfer to shuttle buses that connected to the main subway network to continue their journey.,[11] making the line sparsely used in 2011. The situation did not improve on April 29, 2012 when the Beijing subway exceeded a record 8 million daily riders, with the daily ridership of Line 9 being only 46,300 as it was still isolated from the rest of the network.[12]

On December 30, 2012, the original northern section from the Beijing West railway station to the National Library entered into operation. This finally connected Line 9 and the Fangshan Line to the rest of the subway network and made all major Beijing train stations accessible by subway.[13] The underground connections for the transfer between Line 9 and Line 1 were not completed at the opening of the Line 9 extension.[14] Between December 2012 and December 2013, Line 9 skipped Military Museum station.[15] Line 9's passenger traffic began to grow rapidly after the northern section went into operation. As of January 2013, the average daily passenger traffic was already three times higher than in December 2012,[16] at 220,000 rides.[17] The Line 1 to Line 9 transfer was completed at the Military Museum Station on December 21, 2013.

Line 9 is served by a fleet of 37 6-car DKZ33 trains built by CNR Changchun.[19]

Model	Image	Manufacturer	Year Built	Amount in Service	Fleet Numbers	Depot
DKZ33		CRRC Changchun Railway Vehicles	2011, 2019	37	09 001–09 037	Guogongzhuang

• Line 9
• 
  Liuliqiao station platform
• 
  Liuliqiao station concourse
• 
  Guogongzhuang station platform