ABSTRACT
Latvia shares borders with Estonia to the north, Russia to the east, Belarus to the southeast, and the Baltic Sea and Gulf of Riga to the west comprise a coastline of 531km. Between 2500 and 1500 B.C., the Finno-Ugric and proto-Baltic tribes settled on Baltic shores. Survey activities in Latvia began with Tenner’s first-order network of 1820–1832 in Semgallen and Courland and were published by Czarist Russia in 1843 and 1847. In 1943, extensive surveys were executed along the Latvian–Russian border for the final connection of the Latvian triangulation with the Pulkovo system. According to the decision of IAG Reference Frame Sub-commission for Europe, the EVRF2007 solution as the vertical reference has to be deployed in EU countries. LSU’s Center for GeoInformatics had acquired an absolute gravity meter along with a couple of relative gravity meters and various related instruments and vehicles with the same objective for the State of Louisiana.
