Heaven Lake (천지 (Ch'ŏnji or Cheonji) in Korean; 天池 (Tiānchí) in Chinese; Tamun omo or Tamun juce in Manchu) is a crater lake on the border between China and North Korea. It lies within a caldera atop the volcanic Baekdu Mountain, a part of the Baekdudaegan mountain range and the Changbai mountain range.