Stock Photo - Indian passengers travelling in the Nilgiri Mountain Railway (steam train) descending through the Nilgiri Mountains from Coonoor to Mettupalayam. India, Tamil Nadu 2005. - Info: The Nilgiri Mountain Railway (NMR) is the only rack railway in India and connects the town of Mettupalayam with the hill station of Udagamandalam (Ooty), in the Nilgiri Hills of southern India. The construction of the 46km long meter-gauge singletrack railway in Tamil Nadu State was first proposed in 1854, but due to the difficulty of the mountainous location, the work only started in 1891 and was completed in 1908. This railway, scaling an elevation of 326m to 2,203m and still in use today, represented the latest technology of the time. In July 2005, UNESCO added the NMR as an extension to the World Heritage Site of Darjeeling Himalayan Railway.