The Struve Geodetic Arc measurement point (1841) is located at Hyypänmäki, the highest point in Hailuoto (31 meters above sea level). The location of the point is not marked on the terrain, as the sand constantly changes the shape of the hill, and there are no measurement stones in the vicinity.

Read more about the measurement points on the National Land Survey of Finland's website under Struve Geodetic Arc.

The Struve Geodetic Arc is a triangulation chain between the Arctic Ocean and the Black Sea. It was used to determine the shape and size of the Earth in the 19th century. The Struve Geodetic Arc is listed as a UNESCO World Heritage site. Of the measurement points selected as World Heritage sites, six are located in Finland. The measurement points are historically significant and also offer excellent viewpoints. (Source: National Land Survey of Finland, March 9, 2021)