It is separated from Fukien Province on the mainland China by the Taiwan Straits. The island measures 377 km long and 142 km wide at its widest point. The Central Mountain Range slopes gently to a broad and fertile plain in the west. In the east, the mountains descend precipitously to the Pacific. The island's uplands are so extensive that only about one-fourth of Taiwan is arable.
Shorelines are fairly straight and good natural harbors few.
Rivers are short and useful for power generation, but not for navigation. The Kinmen and Matsu, with 182 square kilometers, are two island groups just off the mainland China.