"4000米" refers to an elevation of 4,000 meters above sea level. This height is significant in mountaineering and geography, as it often marks the transition from lower altitudes to high-altitude environments. At this elevation, the air pressure decreases, which can affect breathing and physical performance. Many notable mountains, such as Mount Kilimanjaro and Mount Elbrus, reach or exceed this height. Climbing to 4,000 meters requires proper acclimatization and preparation, as the risk of altitude sickness increases. This elevation is also home to unique ecosystems and wildlife adapted to harsh conditions.