Core Points - The article highlights the significance of the Chinese vertical datum point located in Qingdao, which serves as the national reference for elevation measurements, established in 1957 and maintained by dedicated personnel over the decades [1][4][10] Group 1: Importance of the Vertical Datum Point - The vertical datum point, established on Mount Guanshan in Qingdao, is crucial for unifying elevation measurements across China, allowing for consistent mapping and engineering projects [3][4] - The height of the vertical datum point is precisely measured at 72.260 meters, which is used as the baseline for all elevation calculations in the country [2][4] Group 2: Historical Context and Development - Prior to the establishment of the unified vertical datum point, multiple reference points existed, leading to inconsistencies in elevation data across regions, sometimes differing by 50 to 60 meters [3][4] - The selection of Qingdao as the location for the vertical datum point was based on its geographical advantages, including stable geological conditions and a long history of tidal observations dating back to 1898 [3][4] Group 3: Maintenance and Management - The management of the vertical datum point has been entrusted to the Qingdao Surveying and Mapping Research Institute since 1963, with dedicated personnel ensuring its upkeep and protection [4][5] - The current caretakers utilize modern technology, including geographic information systems and big data, to enhance the management and protection of the vertical datum point [7] Group 4: Contribution to National Development - The vertical datum point has facilitated the development of a comprehensive elevation network across China, supporting various sectors including infrastructure, transportation, and urban planning [8][9] - The surveying team is actively involved in providing comprehensive surveying services for urban projects, including the Qingdao urban rail transit system, ensuring safety and efficiency in construction [9]