Taiwan, officially the Republic of China (ROC), is a country in East Asia. It shares maritime borders with the People's Republic of China (PRC) to the northwest, Japan to the northeast, and the Philippines to the south. The main island of Taiwan has an area of 35, 808 square kilometres (13, 826 sq mi), with mountain ranges dominating the eastern two-thirds and plains in the western third, where its highly urbanised population is concentrated. The capital is Taipei, which, along with New Taipei and Keelung, forms the largest metropolitan area of Taiwan. Other major cities include Kaohsiung, Taichung, Tainan and Taoyuan. With 23. 45 million inhabitants, Taiwan is among the most densely populated countries in the world. Austronesian-speaking ancestors of Taiwanese indigenous peoples settled the island around 6, 000 years ago. In the 17th century, large-scale Han Chinese immigration to western Taiwan began under a Dutch colony and continued under the Kingdom of Tungning. The island was annexed in 1683 by the Qing dynasty of China, and ceded to the Empire of Japan in 1895. The Republic of China, which had overthrown the Qing in 1911, took control of Taiwan on behalf of the World War II Allies following the surrender of Japan in 1945.