• Mr Struve in a nutshell
• Struve Geodetic Arc – from the Danube Delta to the shores of the Arctic Ocean
• Arc measurement
• View the Struve Geodetic Arc on the map
• World Heritage Sites in Finland

Struve Geodetic Arc – from the Danube Delta to the shores of the Arctic Ocean

At the beginning of the 19th century, the astronomer Friedrich Georg Wilhelm Struve led an expedition which was to carry out a triangulation survey across the border states of the Russian empire. Measurements of the triangulation chain known as the Struve Geodetic Arc took place between 1816 and 1855.

Viewed on a map, the Struve Geodetic Arc consists of 258 main triangles, 265 station points and 60 subsidiary points. The northernmost point is located near Hammerfest in Norway and the southernmost point near the Black Sea in the Ukraine.

The Struve Geodetic Arc has served as a model example of the triangulation technique. In Struve’s days, science and technology evolved rapidly, and he had access to the latest scientific and technological achievements of this time. His measurements are surprisingly accurate, considering when they were made.

The project had a scientific objective: to obtain information about the shape of the Earth. The results also had a unique value from the perspective of defence – a fact which in all likelihood helped loosen the purse strings of sponsors such as the Imperial Russian Army.

The measurements have been since used for many scientific purposes. In many of the countries involved, the measurements taken by Struve's expedition laid the groundwork for mapping. In Finland, which at the time was still under Russian rule, the Struve Geodetic Arc finally connected the triangulation chains of the northern and southern parts of the Russian Empire. The NLS later carried out triangulation surveys in the first half of the 20th century, finally completing the survey covering the whole of Finland in the 1960s.

When it was originally measured, the Struve Geodetic Arc went through the territory of two countries – Russia and Sweden. Now it runs through ten states: Norway, Sweden, Finland, Russia, Estonia, Latvia, Lithuania, Belarus, the Republic of Moldova and the Ukraine. A total of 34 stations points have been selected for protection. In Finland the Struve Geodetic Arc is also known as the Russo-Scandinavian meridian arc.