Shanghai is a direct-administered municipality and the most populous urban area in China. It has a population of 29,558,908 in the urban area as of 2025. The city is located on the Chinese shoreline on the southern estuary of the Yangtze River, with the Huangpu River bisecting the city. Shanghai is a global center for finance, business and economics, research, science and technology, manufacturing, transportation, tourism, and culture. The Port of Shanghai is the world's busiest container port. As of 2022, the Greater Shanghai metropolitan area was estimated to produce a gross metropolitan product (nominal) of nearly 13 trillion RMB ($1.9 trillion). Originally a fishing village and market town, Shanghai grew to global prominence in the 19th century due to domestic and foreign trade and its favorable port location. The city was one of five treaty ports forced to open to trade with the Europeans after the First Opium War, with the Shanghai International Settlement and French Concession subsequently established. The city became a primary commercial and financial hub of Asia in the 1930s. During the Second World War, it was the site of the Battle of Shanghai.