Lake Ilmen (Russian: И́льмень, IPA: [ˈilʲmʲɪnʲ]) is a large lake in the Novgorod Oblast of Russia. A historically important lake, it formed a vital part of the medieval trade route from the Varangians to the Greeks. The city of Novgorod - which is a major trade-center of the route - lies six kilometers below the lake's outflow.