The fortress is renowned for its defense against the Mongol army for 36 years before the fall of the Southern Song Dynasty (1127-1279). The location is considered to have witnessed a turning point in world history because Mongke Khan, the fourth supreme khan of the Mongol Empire, died during the siege, and the westward expansion of the Mongol army into Europe halted.

"It's a beautiful place and quite a meaningful place in history as well," said Calum T. M. Nicholson, director of research at the Danube Institute in Hungary. "It's interesting that the Khan who died here while invading this fortress caused everyone to leave Europe."