Karakorum was the capital of the Mongol Empire between 1235 and 1260 and of the Northern Yuan dynasty in the late 14th and 15th centuries. Its ruins lie in the northwestern corner of the Övörkhangai Province of modern-day Mongolia, near the present town of Kharkhorin and adjacent to the Erdene Zuu Monastery, which is likely the oldest surviving Buddhist monastery in Mongolia. They are in the upper part of the World Heritage Site Orkhon Valley.