CHENGDU, March 27 (Xinhua) -- Construction of the Chengdu-Zigong high-speed railway project, the first high-speed railway with a speed of 350 km per hour in southwest China's Sichuan Province, started Wednesday.

According to Sun Yun, chairman of Sichuan Railway Industry Investment Group Co., Ltd., the southbound high-speed rail project is an important part of the country's high-speed rail network consisting of eight main north-south lines and eight main east-west lines.

The high-speed rail starts from Chengdu East Railway Station in the north and ends at Zigong East Railway Station in the south of Sichuan. The length of the main line measures 176.9 km, with an estimated total investment of 36 billion yuan (5.35 billion U.S. dollars) and a construction period of four years.

The railway line will be linked to the Zigong-Yibin high-speed railway and the whole line from Chengdu via Zigong to Yibin will be fully completed and opened to traffic in 2023, forming a major high-speed rail corridor linking Southeast Asia to Sichuan.

Sun said the high-speed railway will not only promote the regional economic and social development of Sichuan, Chongqing, Yunnan and Guizhou, but also support Sichuan's integration into the construction of the Belt and Road and the Yangtze River Economic Belt.