NGARI,?Tibet?-- Buses on Monday started operating in Ngari prefecture, the highest area in Southwest China's Tibet autonomous region known as the "world's rooftop".

Six buses started operating along three lines in Sengye Tsangpo township, where the government seat of the prefecture is located, after local authorities made an investment of over 2 million yuan ($313,200).

The bus service was launched due to the fast urban and economic development in Sengye Tsangpo, which has become a business and transport hub in west Tibet, said Losang, vice commissioner of Ngari prefecture.

Many residents cheered the opening of the bus lines. Chodron, a 63-year-old Tibetan, described taking the bus trip in her hometown an "unbelievable experience".

Ngari, with an average altitude of 4,500 meters above sea level, has been lagging behind in transportation infrastructure. In 2011, a highway started linking the regional capital of Lhasa and Sengye Tsangpo as the first highway to cross the prefecture.