<P> A second airport open for commercial flights has been suggested either by expansion of Meerut Airport or construction of a new airport in Greater Noida . The Taj International Airport project in Jewar has been approved by the Uttar Pradesh government . </P> <P> Delhi has the highest road density of 2103 km / 100 km in India . It is connected to other parts of India by five National Highways: NH 44, 2, 48, 9 and 24 . The city's road network is maintained by MCD, NDMC, Delhi Cantonment Board, Public Works Department (PWD) and Delhi Development Authority . </P> <P> Buses are the most popular means of road transport catering to about 60% of Delhi's total demand . Delhi has one of India's largest bus transport systems . In 1998, the Supreme Court of India ruled that all public transport vehicles in Delhi must be fuelled by compressed natural gas (CNG) to tackle increasing vehicular pollution . The state - owned Delhi Transport Corporation (DTC) is a major bus service provider which operates the world's largest fleet of CNG - fuelled buses . In addition, cluster scheme buses are operated by Delhi Integrated Multi-Modal Transit System (DIMTS) with the participation of private concessionaires and DTC . In December 2017, the DTC and cluster buses carried over 4.19 million passengers per day . Kashmiri Gate ISBT, Anand Vihar ISBT and Sarai Kale Khan ISBT are the main bus terminals for outstation buses plying to neighboring states . Delhi's rapid rate of economic development and population growth has resulted in an increasing demand for transport, creating excessive pressure on the city's transport infrastructure . To meet the transport demand, the State and Union government constructed a mass rapid transit system, including the Delhi Metro . Delhi Bus Rapid Transit System runs between Ambedkar Nagar and Delhi Gate . </P> <P> Personal vehicles especially cars also form a major chunk of vehicles plying on Delhi roads . As of 2007, private vehicles account for 30% of the total demand for transport . Delhi has the highest number of registered cars compared to any other metropolitan city in India . Taxis, auto rickshaws, and cycle rickshaws also ply on Delhi roads in large numbers . As of 2008, the number of vehicles in the metropolitan region, Delhi NCR, was 11.2 million (11.2 million). In 2008, there were 85 cars in Delhi for every 1,000 of its residents . In 2017, the number of vehicles in Delhi city alone crossed one crore mark with the transport department of Delhi Government putting the total number of registered vehicles at 1, 05, 67,712 till May 25 of the year . </P>

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