Struve Geodetic Arc

It was measured in 1816–1855, and the project was led by F.G.W. Struve. The Struve Arc is a chain of survey triangulations stretching over 2,820 km. It runs close by the 26th meridian east from Hammerfest by the Arctic Ocean in Norway all the way to the Black Sea in Izmail, Ukraine.

The arc of measurements consisted of 258 main triangles with 265 main station points and 60 subsidiary station points. Nowadays, the arc runs through ten countries: Norway, Sweden, Finland, Russia, Estonia, Latvia, Lithuania, Belarus, Moldova and Ukraine.

World Heritage Site

The ten countries along the arc have worked in co-operation to find, review and mark the points of the arc. A total of 34 station points of the Struve Arc have been selected and conserved to represent the entire measurement. These sites are located in all the countries along the arc but the number of stations vary according to how many stations each country originally had and how they have been preserved. In every country, only the most prominent sites have been selected. The Tartu Observatory in Estonia and the Church of Alatornio in Finland are the only buildings that were used as measurement stations.

Also both terminals, Fuglenaes on the shores of the Arctic Ocean and Staro-Nekrassowka near the Black Sea, are included. Finland has six conserved station points.

The chosen 34 station points represent the Struve Arc officially, but also the other remaining stations have been conserved according to the national regulations of each country.

The Struve Arc is the most significant accomplishment of technology and science of its time. It was considered to be a prime example of survey triangulation still in the late 1900s. The Struve Arc was added to the UNESCO World Heritage List in July 2005.

Aavasaksa – “Avasaksa”

The Aavasaksa station point, called ‘Avasaksa’ by the measurers, was measured in 1845 on the highest point of the fell. The crosses carved in the rock to mark the station point are now underneath the observation tower built in 1969.

The measurers of the Struve Arc created detailed reports of their work. Of the carved crosses, one was the central station point. The second point was measured 2.4 then French royal feet (0.77 metres) west of the central station point and the third point 3.2 French royal feet (1.04 metres) east of the central station point.

The geodesists did not choose Aavasaksa as the station point because of its breathtaking scenery but for practical reasons: you could easily see the next points from the top of the fell.