Taiwan, officially the Republic of China (ROC), is an island country located in East Asia. The main island of Taiwan, formerly known in the West as Formosa, makes up 99% of the land area of the territories under ROC control. The main island measures and lies some across the Taiwan Strait from the southeastern coast of the People's Republic of China (PRC). The East China Sea lies to the north of the island, the Philippine Sea to its east, the Luzon Strait directly to its south and the South China Sea to its southwest. The ROC also controls a number of smaller islands, including the Penghu archipelago in the Taiwan Strait, the Kinmen and Matsu Islands near the PRC's coast, and some of the South China Sea Islands. Geologically, the main island comprises a tilted fault block, characterized by the contrast between the eastern two-thirds, consisting mostly of five rugged mountain ranges running parallel to the east coast, and the flat to gently rolling plains of the western third, where the majority of the population resides. Several peaks exceed 3,500 m in height - the highest, Yu Shan at , makes Taiwan the world's fourth-highest island. The tectonic boundary that formed these ranges remains active, and the island experiences many earthquakes, a few of them highly destructive. There are also many active submarine volcanoes in the Taiwan Straits. The climate ranges from tropical in the south to subtropical in the north, and is governed by the East Asian Monsoon. On average, four typhoons strike the main island each year. The heavily forested eastern mountains provide a habitat for a diverse range of wildlife, while human land use in the western and northern lowlands is intensive. Physical boundaries The total land area of Taiwan is , slightly larger than Belgium. It has a coastline of . The ROC claims an exclusive economic zone of with and a territorial sea of . Taiwan proper, the main island of the archipelago, was known in the West until after World War II as Formosa, from the Portuguese Ilha Formosa (), "beautiful island". It is long and wide, and has an area of . The northernmost point of the island is Cape Fugui in New Taipei's Shimen District. The central point of the island is in Puli Township, Nantou County. The southernmost point on the island is Cape Eluanbi in Hengchun Township, Pingtung County. The