The
Delhi Metro is a
metro system serving
Delhi and its satellite cities of
Faridabad,
Gurgaon,
Noida and
Ghaziabad in
National Capital Region in India. Delhi Metro is the world's
12th largest metro system in terms of both length and number of stations. A member of the
Nova Group of Metros, the network consists of five colour-coded regular lines and the faster
Airport Express line, with a total length of serving
160 stations (including 6 on Airport Express line). The system has a mix of underground, at-grade, and elevated stations using both broad-gauge and standard-gauge. The metro has an average daily ridership of 2.4 million passengers, and, as of August 2010, had already carried over 1.25 billion passengers since its inception.