What subsidiaries does China Railway Tunnel Group Co., Ltd. have? Is limited company the head office?

China Railway Tunnel Group is the largest enterprise group in the field of tunnel and underground engineering in China. 1In May, 1978, the Ministry of Railways reported to the State Council for approval, and established 450 1 engineering headquarters in Luoyang, Henan. In June of the same year 10, the State Council approved the reorganization of 450 1 Engineering Headquarters into the Tunnel Engineering Bureau of the Ministry of Railways. 1September, 1999, the Tunnel Engineering Bureau was decoupled from the Ministry of Railways and renamed as. In May, 20001year, the Tunnel Engineering Bureau reformed the company system, and established China Railway Tunnel Group with China Railway Tunnel Group Co., Ltd. as the core enterprise, which integrates four functions of survey and design, construction, scientific research and development and machine maintenance, and is affiliated to China Railway Corporation. At present, the Group has 10 construction subsidiaries, 1 survey and design institutes, 1 technology centers, 6 regional headquarters in Beijing, Nanjing, Guangzhou, Xi, Chengdu and Wuhan, 300 projects under construction and construction teams all over the country.