system that connects all parts of the state, via highway roads, railway lines, airports, and seaports. Road The state is served by an extensive road network, providing links between urban centers, agricultural market-places and rural areas. There are 29 national highways in the state, covering a total distance of . The state is also a terminus for the Golden Quadrilateral project that connects Indian metropolises like (New Delhi, Mumbai, Bengaluru, Chennai and Kolkata). The state has a total road length of , of which are maintained by the Highways Department. This is nearly 2.5 times higher than the density of all-India road network. The major road junctions are Chennai, Vellore, Madurai, Trichy, Coimbatore, Tiruppur, Salem, Tirunelveli, Thoothukudi, Karur, Kumbakonam, Krishnagiri, Dindigul and Kanniyakumari. Road transport is provided by state owned Tamil Nadu State Transport Corporation and State Express Transport Corporation. Almost every part of the state is well connected by buses 24 hours a day. The state accounted for 13.6 per cent of all accidents in the country with 66,238 accidents in 2013, 11.3 per cent of all road accident deaths and 15 per cent of all road-related injuries, according to data provided by the Ministry of Road Transport and Highways. Although Tamil Nadu accounts for the highest number of road accidents in India, it also leads in having reduced the number of fatalities in accident-prone areas with deployment of personnel and a sustained awareness campaign. The number of deaths at areas decreased from 1,053 in 2011 to 881 in 2012 and 867 in 2013. Rail Tamil Nadu has a well-developed rail network as part of Southern Railway. Headquartered at Chennai, the Southern Railway network extends over a large area of India's southern peninsula, covering the states of Tamil Nadu, Kerala, Puducherry, a small portion of Karnataka and a small portion of Andhra Pradesh. Express trains connect the state capital Chennai with Mumbai, Delhi, and Kolkata. Puratchi Thalaivar Dr. M.G. Ramachandran Central Railway Station is the gateway for trains towards the north whereas Chennai Egmore serves as the gateway for the south. Tamil Nadu has a total railway track length of and there are 532 railway stations in the state. The network connects the state with most major cities in India. The Nilgiri Mountain Railway (part of the Mountain Railways of India) is one of the UNESCO World Heritage Site connecting Ooty on the hills and Mettupalayam in the foothills