Geographical Features -- Matsu

As introduced by the Yearbook of the Republic of China:

Situated outside the mouth of China's Minjiang River, the Matsu Islands form the northern anchor of the offshore defense line. The main island of the complex is Nangan, but it is more commonly known as Matsu, which is the name of the major port of the island. Matsu is 114 nautical miles northwest of Keelung, the port city on the northern tip of Taiwan, and is the same distance north from the Kinmen Islands. There are two harbors in Nangan: Fu-ao and Matsu. Other major islands of the group are Beigan, Gaodeng, Liang Island, Daciou, Siaociou, Dongyin, Siyin, Dongjyu, and Sijyu. Nangan is the largest, with an area of 10.4 sq. km. Gaodeng is located only 5.5 nautical miles (9,250 meters) off the coast of China.

The islands are composed of an uplift of igneous rock. Granite is the Matsu area's major natural resource. The climate is characterized by monsoon rains from August to December and typhoons during the summer.

Although the hilly terrain is not well-suited for agriculture, ten reservoirs, 15 sea dikes, and two ponds have been constructed and 320 irrigation wells drilled to facilitate farming. Vegetable production has reached the point of self-sufficiency.