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Workers clean snow on a tunnel bridge on the Ya'an-Kangding expressway in southwest China's Sichuan Province, Dec. 30, 2018. An expressway linking Ya'an and Kangding in southwest China's Sichuan Province went into trial operation Monday morning, marking the total length of expressways in the province at 7,238 km. The construction of the expressway was completed nine months ahead of schedule. It will be the second highway into the Ganzi Tibetan Autonomous Prefecture of Sichuan after the National Highway 318, which leads to Lhasa, capital of Tibet Autonomous Region, said the provincial department of transportation. The newly completed route will enable passengers to travel from Chengdu to Kangding, capital of Ganzi, in only three and a half hours. (Xinhua/Jiang Hongjing)

CHENGDU, Dec. 31 (Xinhua) -- An expressway linking Ya'an and Kangding in southwest China's Sichuan Province went into trial operation Monday morning, marking the total length of expressways in the province at 7,238 km.

The construction of the expressway was completed nine months ahead of schedule. It will be the second highway into the Ganzi Tibetan Autonomous Prefecture of Sichuan after the National Highway 318, which leads to Lhasa, capital of Tibet Autonomous Region, said the provincial department of transportation.

The newly completed route will enable passengers to travel from Chengdu to Kangding, capital of Ganzi, in only three and a half hours.

The total construction length of the Ya'an-Kangding expressway is about 135 km and costs about 23 billion yuan (about 3.3 billion U.S. dollars).

As it climbs from the Sichuan Basin several hundred meters above sea level to the edge of Qinghai-Tibet Plateau, the expressway's cumulative ascent exceeds 2,000 meters, said the department.

The construction of the expressway started in September 2014 and faced challenging geographic conditions including the narrow and steep terrain. One of its mountain tunnels even passes through 13 earthquake fault zones.