The Darjeeling Himalayan Railway (DHR), popularly known as the Toy Train, is an integral part of the northern hills of West Bengal. Opened gradually between 1879 and 1881, the two feet (610 mm) gauge railway, is an engineering marvel. In its 88km long journey, the train ascends from100 m (328 ft) above sea level at New Jalpaiguri to about 2,200 m (7,218 ft) at Darjeeling, using six zigzags and five loops to gain altitude. In 1999, the DHR became the second railway in the world to win the UNESCO World Heritage Site status (which was later extended to two other railways of India and together they are known as the Mountain Railways of India).