The White Crane Beam was formed naturally during the orogeny, with a length of about 1600 m and a width of about 10 to 15 m.. It extends from east to west, parallel to the Yangtze River. The elevation of the back is about138m, which is 2-3m higher than the local lowest water level all the year round. With the alternation of dry season and rainy season every year, summer hides in winter. The beam body is divided into upper, middle and lower sections, and the inscription is located on the beam body. The middle section is about 220m, and the width is about15m. So far, there are about 165 sections, about 30,000 words. The inscription began in the first year of Tang Guangde (AD 763) and ended in 1963. The earliest known date is the fourth year of Kaibao in the Northern Song Dynasty (AD 97 1).
The 18 stone fish carving on the beam records the hydrological conditions of the Yangtze River in 72 dry years since 1200, which systematically reflects the water level evolution of the upper reaches of the Yangtze River in dry years, and provides important physical evidence for studying the historical laws of Yangtze River hydrology, regional and global climate change. The construction of Gezhouba and Three Gorges Water Control Project once relied on this, and Baiheliang has also become a "Yangtze River Paleohydrological Station" and a "world hydrological data treasure house".
Baiheliang inscription is the earliest known hydrological inscription with the longest duration and the largest number in the world. UNESCO called Baiheliang "the only well-preserved ancient hydrological station in the world".
In the inscription of Baiheliang, there is a stone fish, which is the earliest inscription of Xiaoshui. Its eyes are just the zero water level in the middle and upper reaches of the Yangtze River, which is earlier than the water level observation record of Wuhan Jianghan Pass Water Gauge, the first water gauge erected on the Yangtze River 1865 years ago. There is a local saying that "the weather is good and the stone fish comes out of the water". It is said that if stone fish surface in the dry season of winter, the next year will be a good year. "Stone fish coming out of the water" is a "good omen" for local people to look forward to a bumper year.
Literati and writers of all ages like to carve characters on Baiheliang, making it an "underwater forest of steles" integrating literature, calligraphy, painting and stone carving. The inscriptions with more than 30,000 words in eight styles left by more than 30,000 literati in the Liang Dynasty have amazing artistic value, among which Huang Tingjian, a great writer and calligrapher in the Song Dynasty, is the most famous.
Huang Dejian, director of Chongqing Fuling Museum, said that Bai Heliang's inscription has important scientific, historical and artistic values and is a well-deserved "Chinese treasure".