Neman, Niemen or Nemunas is a river in Europe that rises in central Belarus and flows through Lithuania then forms the northern border of Kaliningrad Oblast, Russia's western exclave, which specifically follows its southern channel. It drains into the Curonian Lagoon, narrowly connected to the Baltic Sea. The 937 km long Neman is a major Eastern Europe…Neman, Niemen or Nemunas is a river in Europe that rises in central Belarus and flows through Lithuania then forms the northern border of Kaliningrad Oblast, Russia's western exclave, which specifically follows its southern channel. It drains into the Curonian Lagoon, narrowly connected to the Baltic Sea. The 937 km long Neman is a major Eastern European river. It flows generally west to Grodno within 12 kilometres of the Polish border, north to Kaunas, then westward again to the sea.