Google chairman Eric Schmidt recently visited North Korea to promote Internet usage independence in North Korea. Shortly after that, it was revealed that Google Earth is being used to pinpoint North Korean labor camps by human rights activists and bloggers. Dozens of prison camps were hidden within North Korea and they were outed by Google Earth. The Google Earth map highlights guard posts, shacks, compounds, and some of the prisoner locations. In North Korea, it is believed that there are as many as 250,000 political prisoners. There may also be coal mines and crude burial grounds highlighted on the map.