Heifengkou, or Black Wind Pass, is a narrow pass on the northern slope of Changbai Mountain, not far from Changbai Grand Waterfall. Gale-force winds blow through it incessantly, occasionally reaching gale force 5 (on a normal Beaufort Scale of 1-12, though the scale extends to 17 when applied to typhoons), when small black lava stones are picked up and thrown by the wind. Despite the gusty conditions, one can get a beautiful panoramic view of Changbai Grand Waterfall from the summit of Heifengkou.