The Delhi Metro is a metro system serving Delhi and its satellite cities of Faridabad, Gurugram, Noida and Ghaziabad in National Capital Region in India. Delhi Metro Rail Corporation Limited (DMRC), a state-owned company with equal equity participation from Government of India and Government of Delhi, built and operates the Delhi Metro.Delhi Metro is the world's 12th longest metro system in length and 16th largest in ridership. A member of CoMET, the network consists of five colour-coded regular lines and the faster Airport Express line, with a total length of 218km serving 164 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 power output is supplied by 25-kilovolt, 50-hertz alternating current through overhead catenary. The trains are usually of four, six, and eight-coach length. DMRC operates over 3,000 trips daily, with first trains starting at around 05:00 and last at 23:30.