Hoeryong concentration camp
North Korea
Hoeryong concentration camp (Haengyong concentration camp or Camp 22) was a concentration and death camp in North Korea that was reported to have been closed in 2012. The official name was Kwalliso (penal labour colony) No. 22. The camp was a maximum security area, completely isolated from the outside world. In 2012, satellite image analysis and reports indicated major changes including its reported closure.
Prison data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).