Workers pave asphalt on G213 road at Qilian Mountains region on Wednesday. Photo: Shi Jiamin

A 62.77-kilometer road on high altitude connecting Gansu and Qinghai provinces in Northwest China started asphalt paving on Wednesday, aiming to shorten the travel time by almost two-thirds next year, which will facilitate tourist and freight transport between the two provinces.

Starting from Sunan county in Gansu, an important point on the ancient Silk Road where Asian and European civilizations converged, the G213 road project ends at Qilian county in Qinghai and stretches across Qilian Mountains that are bounded by deserts on three sides.

For years, China has introduced various favorable policies to beef up the development of its western region, in which infrastructure connectivity plays a critical role.

Workers pave asphalt on G213 road at Qilian Mountains region on Wednesday. Photo: Zhang Dan/GT

As a thoroughfare under the Belt and Road Initiative within China, the project will shorten the driving time between the two counties from seven to two and half hours.

Sitting at the altitude of about 4,200 meters above the sea level, the No. 5 section of the project, constructed by China Tiesiju Civil Engineering Group, is the most difficult part to build. It is one of the highest roads under construction in China.

"Most of our 400 construction workers come from Qinghai, Gansu and Sichuan provinces as they can better cope with the hostile environment compared with people from inland plains," Ma Zhikui, project manager of the No. 5 section, told the Global Times on Wednesday, citing a survey which shows the labor and machine efficiency in plateau region is 42 percent lower compared with plains.

A worker from Central China's Henan said he had to inhale extra oxygen in the first month when coming to work here, as altitude sickness may cause headache, breathing difficulties, fever, and even death.

A worker is inhaling extra oxygen at the construction site due to altitude sickness. Photo: Zhang Dan/GT

The oxygen content of the air at the project is about 11 percent, almost half of the general level of 21 percent.

Another difficulty in building the road is the low temperature in the Qilian Mountains region composed of many parallel mountains with glaciers on the top, which shortens the construction period to just five months (May to September) in a year.

"In order to pave asphalt in the region, we elevate the temperature of the asphalt by 10 degrees Celsius so that it won't make an impact on the road quality," Ma noted, adding the lowest temperature in the region hits minus 30 degrees Celsius.

Disrupted by the COVID-19 epidemic, the construction was suspended for two months due to a lack of raw material supplies and workers, and is now accelerating the construction pace.