Tianjin, formerly known in English as Tientsin, is a metropolis in northern coastal Mainland China and one of the four national central cities of the country, with a total population of 15,469,500, and is also the world's 6th-most populous city proper. It is governed as one of the four direct-controlled municipalities of the PRC and is thus under direct administration of the central government. Tianjin borders Hebei Province and Beijing Municipality, bounded to the east by the Bohai Gulf portion of the Yellow Sea. Part of the Bohai Economic Rim, it is the largest coastal city in northern China.
Tianjin is one of the four autonomous municipalities along with Beijing, Shanghai and Chongqing, and is an integral part of the Bohai Bay Economic Zone, which is one of the three biggest economic zones in China.
Tianjin is transforming into a hub city for international shipping and logistics, modern manufacturing and research and development.
Tianjin port, as the largest comprehensive and commercial port in North China, provides services to 300 ports in more than 170 countries and regions all over the world. Tianjin International Airport is a major cargo freight center in China. The city is well connected to other major cities by dozens of railroads and expressways. Tianjin is the region's largest financial center.
Tianjin has become the pilot city with the most industrial investment funds in China. Major industries include petrochemical industries, textiles, car manufacturing, mechanical industries, and metalworking.