Weeks after its chairman Eric Schmidt's secretive visit to North Korea, Google has released a detailed map of the isolated state that even labels some of its remote and infamous gulags.

Until now North Korea was pretty much a blank canvas to users of Google's "Map Maker", which creates maps from data that is provided by the public and fact-checked in a similar process to that used by Wikipedia.

Details ... the North Korean capital of Pyongyang on Google Maps.

"For a long time, one of the largest places with limited map data has been North Korea. But today we are changing that," Jayanth Mysore, a senior product manager at Google Map Maker, said in a blog post.

"We know this map is not perfect — one of the exciting things about maps is that the world is a constantly changing place," he said.