Struve Geodetic Arc

A chain of unassuming markers — drilled rocks, cairns, iron crosses, obelisks — records one of science's great collaborative feats. Between 1816 and 1855 the astronomer Friedrich Georg Wilhelm Struve directed a survey triangulation running 2,820 km from Norway's Arctic coast to the Black Sea, producing the first precise measurement of a long meridian arc and sharpening humanity's knowledge of Earth's size and shape. Thirty-four of the original station points, spread through ten countries including Belarus, were inscribed by UNESCO in 2005.