Gunsa Airport in southwest China's Tibet Autonomous Region started operation Thursday, becoming the fourth civil airport on the "Roof of the World."

An Airbus 319 landed at Gunsa Airport, in Ngari Prefecture, at 10:20 AM, marking the airport's formal opening.

The passenger flight from Chengdu, capital of the neighboring Sichuan Province, was operated by Air China's southwestern branch.

Air China will flight would fly from Chengdu to Lhasa and on to Ngari every Tuesday and Friday, said Bao Lida, a press official with the company's southwestern branch based in Chengdu.

"The flight leaves Chengdu at 5:50 AM and arrives Lhasa two hours later," said Bao. "It leaves Lhasa at 8:40 AM and arrives Ngari at 10:20 AM."

The flight distance between Chengdu and Ngari is 2,300 km.

Gunsa Airport sits more than 4,200 meters above sea level and has a 4,500-meter runway. Its annual throughput capacity is expected to reach 120,000 passengers by 2020.

Construction of the airport began in May 2007 and cost an estimated 1.65 billion yuan (US$241.22 million).

Before the airport opened, Ngari was linked to Lhasa only by road and it took three days to cover the 1,600-km route.

Gunsa Airport is the fourth civil airport in Tibet after Gonggar Airport in Lhasa, Bamda Airport in Qamdo Prefecture and Nyingchi Airport.

A fifth airport, Peace Airport in Xigaze, is expected to open in October.

Exactly four years ago, China opened a landmark railway linking Tibet with major cities, including Beijing, Shanghai and Guangzhou.

(Xinhua News Agency July 1, 2010)