Survey Benchmark in Beijing
I always try and find survey markers when I travel. Usually it’s little more than a vaguely interesting ground marker but this one stopped me in my tracks.
Text reads;
Bench Mark Stone
Beijing bench mark is the datum point to compute and measure the alitude of Beijing. All the topographic maps buldings, underground structures pipe networks and vertical control points are designed on the basis of this benchmark.
Made of Han white jade, this Stone is a cuboid which is 1 meter in height and 02 meter in width, and bears the Chinese characters which mean For the Measurement of the Water Level of Beling on one side and "Capital Engineering Bureau on the other side. The original
"Shi" and "Jing" characters disappeared due to the weathering action. The Stone was discovered in the road works in Nanluogu Alley in August 2006.
According to historical records of Beijing Institute of Surveying and Mapping, the height of the peak is 49 meters above sea level. Four meters higher than the northeast corner of the imperial Palace, it was then the highest point of Beijing inner city. This Stone was built during the early period of Republic of China (1914 to 1916) At that time, the Surveying Department of the Capital Engineering Bureau set up 80-odd stones for the measurement of the water level of Beijing and the corresponding precision was up to 1%.At present, there are no more than 3 such stones left in Beijing.