Major construction of the first subway traversing the ancient Chinese city of Xi'an, home of the "terra-cotta warriors," was completed Friday.

This will allow the No. 2 metro line, 26.4 km in length for the first section, to open in 2011 on schedule, said Chen Dongshan, general manager of Xi'an Subway Co. Ltd in capital of northwest China's Shannxi Province.

It runs south-to-north and goes beneath two 600-year-old sites, the Ancient City Wall from the Ming Dynasty (1368-1644) and the Bell Tower. Advanced technologies have been used to reduce noise and vibrations to protect the relics, Chen said.

Facilities were being installed inside all 17 stations of the subway line, which has been constructed since 2006.

Altogether six subway lines with a length of 251 km are planned for Xi'an, with two to be completed before 2015.

Xi'an's history stretches back more than 3,000 years and has been the capital of 13 dynasties of ancient China.

Also on Friday, two new subway lines became operational in Nanjing, capital of east China's Jiangsu Province.

With the extension line of No.1 metro line and No. 2 metro line, the total length of the subway lines in the city was extended from 21.72 km to 85 km, making Nanjing the city with the fourth longest length of subway lines, after Shanghai, Beijing and Guangzhou.

(Xinhua News Agency May 29, 2010)