Struve Geodetic Arc
The Struve Arc is a series of triangulated lines from Hammerfest, Norway to the Black Sea, passing through 10 countries and covering a length of more than 2,820 km. These are the result of a survey carried out between 1816 and 1855 by astronomer Friedrich Georg Wilhelm Struve, which was the first accurate measurement of a long segment of the meridian. This helped to determine the exact size and shape of the Earth and marked an important step in the development of Earth science and topographic mapping. It is an extraordinary example of scientific cooperation between scientists from different countries and cooperation between monarchs for the sake of science. The original arc consisted of 258 main triangles and 265 main stations. The listed sites include 34 original stations, which are variously marked by rock drill holes, iron crosses, stone tablets or constructed obelisks.