a lake system in southeastern Finland with a total area of 4,400 sq km and depths reaching 82 m. The water level fluctuates from 76 to 82 m. The lakes’ basin is tectonic in origin and was broadened and smoothed by a continental glacier. The shoreline is extremely rugged, frequently rocky, and usually covered by forests.
Saimaa Lakes are dotted with many islands and have numerous tributaries. Many rivers empty into the lake; these rivers drain an area of 69,500 sq km. The lake drains through the Vu-oksi River into Lake Ladoga. The highest water levels in Lake Saimaa occur in summer, and the lowest occur in early spring. The lakes are covered with ice from December through May.
The ports of Mikkeli, Lappeenranta, Savonlinna, and Joen-suu are located on Saimaa Lakes, which are joined with the Baltic’s Gulf of Finland by the Saimaa Canal. Lumber is transported on the lakes, and there is fishing and local navigation. There is tourism in the area. The name “Saimaa” sometimes refers to only the southern section of the lake system (area, 1,700 sq km).