Xingkai Lake, located in Jixi City in northeast China's Heilongjiang Province, is a border lake between China and Russia. In winter, the lake surface is frozen for thousands of miles, with the temperature dropping to as low as minus 30 to 40 Celsius degrees. The troops assigned to a border defense brigade under Chinese PLA Northern Theater Command have become accustomed to patrol the lake with the hovercrafts.

(Video Editor: Du Xuanwei)