Composed of more than 25 islands and over 230 reef shoals and sand banks, the Nansha Islands and their adjacent waters encompass 823,000 square kilometers, approximately the size of 80 Hong Kongs or 23 Taiwans. This accounts for more than one quarter of China’s 3-million-square-kilometer marine territory. In addition to the rich fishery resources, in this part of the South China Sea, which may yield a gross catch of 500,000 tons of fish every year. Nansha also has estimated oil resources of 35 billion tons and natural gas resources of 8,300 billion cubic meters.
Known as "the Second Persian Gulf" for its oil and gas reserves, Nansha is also a vital communication line for China′s foreign trade, as 21 out of the country′s 39 navigation routes to other nations go through Nansha.
The first generation of the People′s Liberation Army (PLA) "Nansha guardians〝 set up the reef posts in the 1980s, when UNESCO commissioned China to establish an ocean logical and meteorological observatory