Introduction to Tuofengling Tianchi: Tuofengling Tianchi is a lake formed by water accumulation in the crater after a volcanic eruption. The water surface is 1284m above sea level. The overall shape is "left foot" shape, about 450m wide from east to west and about 800m long from north to south. The formation era was approximately the Middle Pleistocene (about 300,000 years ago).