The Nathula Pass, located about from Gangtok, used to be the primary route of the wool, fur and spice trade with Tibet and spurred economic growth for Gangtok till the mid-20th century. In 1962, after the border was closed during the Sino-Indian War, Gangtok fell into recession. The pass was reopened in 2006 and trade through the pass is expected to boost the economy of Gangtok. The Sikkim government is keen to open a Lhasa–Gangtok bus service via Nathula pass. Sikkim's mountainous terrain results in the lack of train or air links, limiting the area's potential for rapid industrial development. The government is the largest employer in the city, both directly and as contractors.