On this day, 50 years ago, on July 23, 1975 (June 15, 1975, the lunar calendar), my country accurately measured the altitude of the top of Mount Everest to be 8,848.13 meters. Extraordinary Data On July 23, 1975, the China government authorized the Xinhua Agency to announce to the world: my country's surveying and mapping workers accurately measured the altitude of Mount Everest, the world's highest peak, at 8848.13 meters. This accurate data is based on the intersection and observation of our surveying and mapping workers at 10 triangular points 7 to 20 kilometers away from the summit of Mount Everest and an altitude of 5600 to 6300 meters, and obtained a complete plane position and elevation measurement of Mount Everest. After the data, based on the leveling origin established by the Qingdao Yellow Sea Tide Gauge Station, after theoretical research, strict calculation and repeated verification, and deducting the snow depth at the summit, its maximum positive and negative error is less than 0.36 meters. This accurate data was immediately recognized by UNESCO and countries around the world, and soon became authoritative data on world atlases and textbooks. It adds a set of shining numbers to the history of human civilization. This accurate data is conducive to the country's multi-disciplinary investigation and research on Mount Everest, such as geological theory, mountain physiology, atmospheric physics, and water and soil pollution, and provides a reliable basis for my country's scientific research. Yes, 8848.13 meters is by no means an ordinary set of data! It is the note of entrepreneurs composed by my country's surveying and mapping workers with their blood and wisdom, and it is really hard-won.