Taken from Matthew Aid’s own Website – http://www.matthewaid.com/about

All credit for the article goes to Matthew. I have merely lifted if from his site so that others might gain insight through his efforts.

Some interesting Google earth imagery on the links within the text.

Earlier today I posted a blog about the release of satellite imagery about North Korea’s naval bases. In going through the imagery, I discovered that the author of the original piece on cryptome.org missed the North Korean navy’s two most important facilities – the heavily protected submarine bases on the island of Mayang-do at the village of Mayangdori (40.0 N 128-10-36E); and the second sub base which located outside the coastal village of Chahonodongjagu, a/k/a Ch’aho (40-12-56N 128-38-39E). Both bases are situated on the east coast of North Korea.

Estimates vary somewhat, but the North Korean is estimated to have ben 60 and 70 submarines, all of which are diesel-powered coastal subs unsuited for deepwater operations. According to the Defense Intelligence Agency (DIA), the North Korean Navy possesses 4 1960s-vintage Whiskey-class attack subs that rarely go to sea these days, 22 Chinese-made Romeo-class submarines(1,800 tons) which were delivered in the 1970s, 40 domestically produced Sang-O class small coastal submarines (300 tons), and 10 midget submarines used for the clandestine infiltration of agents into South Korea.

Most of these subs are clearly visible in currently available Google Earth satellite imagery. For example, look at this cluster of four Romeo-class subs sharing the same berth at the Mayang-do sub base. If you look just to the south of this berth, you will see two more subs, one of which possibly a Romeo-class sub, docked at the base. About 1,000-meters to the southwest is another heavily protected dock complex housing another cluster of four Romeo-class submarines and possibly two of the smaller Sango-class subs.

Source – Matthew Aid