Tianjing Floating Sky (Big Tianchi Lake) Introduction: Tianchi is 3.4 kilometers long from north to south, 1.5 kilometers at its widest point, 1 kilometer in average width, 9.7 kilometers in circumference; the maximum lake depth is 102 meters, and the average lake depth is 40 meters; lake surface The largest area is 4.9 square kilometers. The lake water is cold and clear, and there are artificially cultivated cold-water scaleless fish.