Set up in 1911, the Tocklai Experimental Station in Jorhat, Assam is the world's oldest and largest tea research station. Its many contributions include the invention of tea machinery and the development of 30 vegetative clones, among other achievements. The transfer of innovative technology to its member estates is carried out through its advisory network that covers as many as 1,076 tea estates occupying 341,049 hectres (3410.49 sq km) of land spread over the South Bank, North Bank, Upper Assam, Cachar, Tripura, the Dooars, Darjeeling and the Terai. Tocklai has its regional R&D centre at Nagrakata in West Bengal.