Brief synthesis
The determination of the size and shape of the world was one of the most important problems of natural philosophy since at least the 4th century B.C. The development, in the 16th century, of a measurement system called “triangulation” improved the ability to determine the size and shape of the world. In this system, long chains of triangles were measured, creating arcs that stretched along hundreds and thousands of kilometres.
The Struve Geodetic Arc is a chain of survey triangulations stretching from Hammerfest in Norway to the Black Sea, through ten countries and over 2,820 km. These are points of a survey, carried out between 1816 and 1855 by several scientists (surveyors) under leadership of the astronomer Friedrich Georg Wilhelm Struve, which represented the first accurate measuring of a long segment of a meridian. This helped to establish the exact size and shape of our planet and marked an important step in the development of earth sciences and topographic mapping. It is an extraordinary example of the development of sciences and of collaboration among scientists from different countries, as well as monarchs, for a common scientific cause.
Prior to the Struve Geodetic Arc, an arc of about 2,400 km had been measured in India by Lambton and Everest (completed in 1845), and a shorter arc in Lithuania by Carl Tenner. Struve, who was working at the Dorpat University (currently University of Tartu in Estonia), decided that he would establish an arc following a line of longitude (meridian) passing through the observatory of the university. The new long arc, later to be known as the Struve Geodetic Arc, was eventually created by connecting earlier, shorter arcs to the southern one measured by Tenner, and their extension to the north and south. The arc thus covered a line connecting Fuglenæs, near Hammerfest at the Arctic Ocean, with Staro-Nekrassowka, near Ismail, on the Black Sea shores, along more than 2,800 km. The original arc consisted of 258 main triangles with 265 main station points. The inscribed property includes 34 of the original station points established by Struve and his colleagues between 1816 and 1851 – four points in Norway, four in Sweden, six in Finland, two in Russia, three in Estonia, two in Latvia, three in Lithuania, five in Belarus, one in Moldova and four in Ukraine. Other preserved sites of the Arc are protected nationally.
These marks take different forms: small holes drilled in rock surfaces, and sometimes filled with lead; cross-shaped engraved marks on rock surfaces; solid stone or brick with a marker inset; rock structures (cairns) with a central stone or brick marked by a drilled hole; individual bricks; as well as especially constructed 'monuments' to commemorate the point and the arc.
The Struve Geodetic Arc is an extraordinary example of the interchange of human values in the form of international scientific collaboration, as well as an outstanding example of a technological ensemble.