Kaunas Reservoir (Lithuanian: Kauno marios) is the largest Lithuanian artificial lake, created in 1959 by damming the Nemunas River near Kaunas and Rumšiškės. It occupies 63.5 square kilometers, which is about 0.1% of the total territory of Lithuania. The reservoir supports the operations of the Kaunas Hydroelectric Power Plant. Its waters cover the Nemunas valley from the river's confluence with Strėva River to the dam, a distance of about 25 kilometers.