At 10:36 a.m. on the 19th, as the China Railway First Group“Kaituo No. 8”shield machine slowly bored southward from the left line of Hanyuandian Station, the section between the Railway Station and Hanyuandian Station on Xi'an Metro Line 4 entered the shield tunneling construction phase.

Metro Line 4 runs from Hangtian Xincheng Station in the Aerospace Industry Base in the south to North Railway Station in the north. It has a total length of about 35.2 kilometers and 29 stations, all of which are underground. The line passes through four administrative districts—Yanta, Beilin, Xincheng and Weiyang—and connects the Aerospace Industry Base, Qujiang New District and the Economic and Technological Development Zone. Major passenger flow hubs along the route include the Railway Station, the Big Wild Goose Pagoda and North Railway Station. The line is laid out from south to north along Hangtian South Road, Shenzhou 4th Road, Furong West Road, Yanta North Road, Heping Road, Jiefang Road, Taihua Road, Fengcheng 8th Road and Mingguang Road.

The civil construction section 11 of Xi'an Metro Line 4, undertaken by the Urban Rail Company of China Railway First Group, includes 2 stations and 2 sections, namely: the Railway Station, Hanyuandian Station, and the Wulukou Station—Railway Station—Hanyuandian Station section. Among them, Hanyuandian Station is a two-level underground island platform station. The Railway Station is being built as a station after the tunnel, and will be carried out in sync with the renovation of the railway station; once completed, it will achieve seamless connection with the railway station.

According to Liang Xijun, project manager of section 11 of Xi'an Metro Line 4, the left line of the shield-tunneled section is 1,003.763 meters long. The huge shield machine must negotiate very slight curves, go downhill and then uphill, with the depth from the surface to the tunnel crown reaching up to 19 meters. At the same time, the shield machine must pass beneath important structures such as the city wall and the Daming Palace National Heritage Park. The construction contractor will avoid the cultural relic protection layer and monitor settlement data of the ground surface and buildings every two hours to ensure stability and safety.

At present, 20 stations on Line 4 have been capped, 8 stations are under main structure construction, and the line has accumulated 14,975 meters of tunneling, accounting for 33% of the total.