No single island in the 19-islet group bears the name of Matsu[.] It is named after a harbor of Nankan, the main island of the group. Nankan is 114 nautical miles west of the northern Taiwan port of Chilung, and 114 nautical miles from Kinmen.

Besides Nankan, other islands in the group are: Peikan, Kaoteng, Tungkun and Hsikun. Kaoteng is only 5 5 nautical miles from the closest mainland point and has been the occasional target of Communist gunners for years. The total land area is only 29 3 sq km. (11.3 sq. mi) Nankan alone has 4.03 sq. km. (10.44 sq mi.) of the total. Located in the fishing area of Fukien, the Matsus are naturally the home of a fishing population. On Nankan there are two good harbors, Fuyu and Matsu.