Taipei is the capital city of Taiwan and its political, economic, and cultural center. It has a population of over 2.6 million people within the city limits. Taipei is located on the northern tip of Taiwan and sits in two narrow river valleys. It has developed into a major industrial and transportation hub with railways, highways, and two international airports connecting it to other parts of the island. Taipei has served as Taiwan's de facto capital since 1949 when the Kuomintang government retreated there after being defeated by the Communists in mainland China during the Chinese Civil War.