NEW DELHI: To improve connectivity with far-flung areas including major tourism centres, the government plans to develop 15,000 km of National Highways (NH) at an estimated cost of Rs 1,90,000 crore.The government has "undertaken detailed review of NH network with a view to improve connectivity in border area including coastal boundaries, major cities of tourism, pilgrimage, minor ports and under developed areas," Minister of Road Transport and Highways, Pon Radhakrishnan informed the Rajya Sabha in a written reply today."This covers about 15,000 km of NHs at an estimated cost of Rs 1,90,000 crore," he said.Projecting the country's highways sector as a "unique opportunity" for investments, government has already rolled out projects worth $93 billion, including the $45-billion flagship road building programme NHDP India has the world's second-largest road network at 4.80 million kms. NHs comprise 2 per cent of total road network carrying 40 per cent of total traffic and 65 per cent of freight and 80 per cent of passenger traffic.