A two-mile-long tunnel has been built 14,000ft high in the mountains as part of Tibet's first railway.

Work on the Yangbajain tunnel, 50 miles north of Lhasa, the Tibetan capital, was finished on 12 October 2003.

The 693-mile line, started in 2001, will cross mountain passes at altitudes of up to 16,737ft.

Workers have to wear wear oxygen masks to cope with the thin air.

The trains will have pressurised air like aeroplanes.

All seven major tunnels on the line have now been completed, according to the Chinese news agency Xinhua.

The railway should start running in 2007.

Information from AP