Heihe–Tengchong Line
The Heihe–Tengchong Line (simplified Chinese: 黑河–腾冲线; traditional Chinese: 黑河–騰衝線; pinyin: Hēihé–Téngchōng xiàn), also called the Aihui–Tengchong Line and internationally as the Hu Huanyong line or Hu line, is an imaginary line coined by Chinese demographer Hu Huanyong (1901–1998) that divides China into two portions with contrasting population densities and climates. It stretches diagonally across China from the city of Heihe, Heilongjiang province in the northeast to Tengchong, Yunnan province in the southwest.