of Taiwan The terrain in Taiwan is divided into two parts: the flat to gently rolling plains in the west, where 90% of the population lives, and the mostly rugged forest-covered mountains in the eastern two-thirds. The eastern part of the island is dominated by five mountain ranges, each running from north-northeast to south-southwest, roughly parallel to the east coast of the island. As a group, they extend from north to south and average about from east to west. They include more than two hundred peaks with elevations of over . The
Central Mountain Range extends from
Su'ao in the northeast to
Eluanbi at the southern tip of the island, forming a ridge of high mountains and serving as the island's principal watershed. The mountains are predominantly composed of hard rock formations resistant to weathering and erosion, although heavy rainfall has deeply scarred the sides with gorges and sharp valleys. The relative relief of the terrain is usually extensive, and the forest-clad mountains with their extreme ruggedness are almost impenetrable. The east side of the Central Mountain Range is the steepest mountain slope in Taiwan, with fault scarps ranging in height from .
Taroko National Park, on the steep eastern side of the range, has good examples of mountainous terrain, gorges and
erosion caused by a swiftly flowing river. The
East Coast Mountain Range extends down the east coast of the island from the mouth of the
Hualien River in the north to
Taitung County in the south, and chiefly consist of sandstone and shale. It is separated from the Central Range by the narrow
Huatung Valley, at an altitude of . Although Hsinkangshan (新港山), the highest peak, reaches an elevation of , most of the range is composed of large hills. Small streams have developed on the flanks, but only one large river cuts across the range. Badlands are located at the western foot of the range, where the ground water level is the lowest and rock formations are the least resistant to weathering. Raised coral reefs along the east coast and the frequent occurrences of earthquakes in the rift valley indicate that the fault block is still rising. The ranges to the west of the Central range are divided into two groups separated by the
Sun Moon Lake Basin in the centre of the island. The
Dadu and
Zhuoshui Rivers flow from the western slopes of the Central Range through the basin to the west coast of the island. The
Xueshan Range lies to the northwest of the Central Mountain Range, beginning at
Sandiaojiao, the northeast tip of the island, and gaining elevation as it extends southwest towards
Nantou County.
Xueshan, the main peak, is high. in northwestern Taiwan The
Yushan Range runs along the southwestern flank of the Central Range. It includes the island's tallest peak, the
Yu Shan ('Jade Mountain') which makes Taiwan the world's
fourth-highest island, and is the highest point in the western Pacific region outside of the
Kamchatka Peninsula,
New Guinea Highlands and
Mount Kinabalu. The
Alishan Range lies west of the Yushan Range, across the valley of the south-flowing
Kaoping River. The range has major elevations between . The main peak, Data Mountain (大塔山), towers . Below the western foothills of the ranges, such as the
Hsinchu Hills and the
Miaoli Hills, lie raised
terraces formed of material eroded from the ranges. These include the
Linkou Plateau, the
Taoyuan Plateau and the
Dadu Plateau. About 23% of Taiwan's land area consists of fertile
alluvial plains and
basins watered by rivers running from the eastern mountains. Over half of this land lies in the
Chianan Plain in southwest Taiwan, with lesser areas in the
Pingtung Plain,
Taichung Basin and
Taipei Basin. The only sizable plain on the east coast is the
Yilan Plain in the northeast. == Climate ==