Far less well-known than the Darjeeling railway, the Nilgiri Railway still rates among the world's best train rides. Listed as a World Heritage site in 2005, this metre gauge line was built in 1899. It is India's only rack railway. It is relatively long for a rack line, and runs through very difficult country. The 21km (12.2 mile) Abt rack section,, from Mettupalaiyam to Coonoor, is steam operated. Graded at 1 in 12½, climbs through the rugged "Blue Hills" of Southern India, with stunning views out over the South Indian plains as it rises. Dramatic cliffs and waterfalls are interspersed with tea and coffee plantations producing some of the world's finest brews. There is a daily service to the hill stations of Coonoor and Ootacamund (or Ooty). There are 208 bridges, 16 tunnels and an unusual "half-tunnel".