Approximately 31 kilometers of railline had been laid by Wednesday on the Qinghai-Tibet railway, the world's highest, since its construction began June 29.

Construction has been going smoothly after a series of technical problems were solved such as high-altitude cold, water and oxygen shortages and frozen earth, according to construction department sources.

Rail-laying hit a record speed of 400 meters per hour without jeopardizing project quality and security, said the sources. The builders laid a 6,001-meter-long section in a matter of 21 hours, records showed.

Zou Zongtong, an official with the rail-laying sector, said that the maximum rail-laying speed on the Qinghai-Tibet rail routewas equivalent to that of an ordinary railway built on a plain thanks to a series of technological innovations.

The management was highly concerned with quality and security while speeding up the construction process, Zou added.

The 1,118-km railway will extend from Lhasa, the capital of theTibet Autonomous Region in southwest China, to Golmud city in Qinghai province in the northwest. It will be the longest and highest railway in the world.

According to the construction schedule, 115 kilometers of railway will be completed by the end of this year.

More than 960 kilometers, or over four-fifths of the railway will be built at an altitude of more than 4,000 meters. And more than half of it will be laid on earth that has been frozen for a long time.

Observers say that China has been thinking of building the Qinghai-Tibet railway for over 50 years. The rapid economic growthand technological advances over the past two decades have given the country enough impetus to complete the project.

( People's Daily July 25, 2002)