50 Lei Geodesic Arc of Struve

The Struve Geodesic Arc was a chain of survey triangulations stretching from Hammerfest in Norway to the Black Sea, conducted between 1816 and 1855 under the direction of Friedrich Georg Wilhelm von Struve to establish the precise shape and size of the Earth. Moldova's section passes through what was then the Russian Empire, and the arc's original survey points — stone markers, drilled rock outcroppings, and iron crosses — were inscribed as a UNESCO World Heritage Site in 2005, which prompted several of the ten participating nations to issue commemorative coins in the years following.