Geography of Taiwan and Green Island to the southeast, separated from the northernmost islands of the Philippines by the Bashi Channel. The islands of Kinmen and Matsu near the coast of Fujian across the Taiwan Strait have a total area of ; the Pratas and Taiping islets in the South China Sea are also administered by the ROC, but are not part of the Taiwanese archipelago. The island of Taiwan was formed approximately 4 to 5 million years ago at a complex convergent boundary between the Philippine Sea Plate and the Eurasian Plate. In a boundary running the length of the island and
History of the Republic of China operations of 1950 were more successful: they led to the Communist conquest of Hainan Island in April 1950, capture of Wanshan Islands off the Guangdong coast (May–August 1950) and of Zhoushan Island off Zhejiang (May 1950). In June 1949 the ROC declared a "closure" of all mainland China ports and its navy attempted to intercept all foreign ships. The closure covered from a point north of the mouth of the Min River in Fujian province to the mouth of the Liao River in Manchuria. Since mainland China's railroad network was underdeveloped, north-south trade depended heavily on sea lanes. ROC naval