The Blue Line was the third line of the Metro to be opened and the first to connect areas outside Delhi. Mainly elevated and partly underground, it connects Dwarka Sub City in the west with the satellite city of Noida in the east, covering a distance of . The first section of this line between Dwarka and Barakhamba Road was inaugurated on 31 December 2005, and subsequent sections opened between Dwarka – Dwarka Sector 9 on 1 April 2006, Barakhamba Road – Indraprastha on 11 November 2006, Indraprastha – Yamuna Bank on 10 May 2009, Yamuna Bank – Noida City Centre on 12 November 2009, and Dwarka Sector 9 – Dwarka Sector 21 on 30 October 2010. This line crosses the Yamuna River between Indraprastha and Yamuna Bank stations, and has India's second extradosed bridge across the Northern Railways mainlines near Pragati Maidan.
