Riyue Mountain, formerly known as Chiling, is a significant stop on the Qinghai-Gansu journey, more than just scenic scenery; it's a natural boundary between heaven and history. At an altitude of over 3,500 meters, standing at the mountain pass, one can simultaneously witness two completely different landscapes: to the east, the fertile fields and villages of the Hehuang Valley; to the west, the vast and desolate grasslands and pastoral areas. The Loess Plateau and the Qinghai-Tibet Plateau meet here, creating a truly wondrous sight. Legend has it that Princess Wencheng, passing through this place, shattered the Sun and Moon Mirror, resolutely embarking on her westward journey to marry a Tibetan king, hence the name Riyue Mountain (Sun and Moon Mountain). The Sun Pavilion and Moon Pavilion stand on opposite peaks, their murals and stone tablets silently recounting this story spanning a thousand years. The statue of Princess Wencheng stands solemnly, and prayer flags flutter in the wind, creating a truly atmospheric scene. Be aware that the mountain is windy and cold; a warm coat is essential. If you're traveling the Qinghai-Gansu Grand Loop, I highly recommend making a special stop to feel the wind blowing through the mountain passes and to understand the rich stories hidden in this land.