The Great Sacandaga Lake (formerly the Sacandaga Reservoir) is a large lake situated in the Adirondack Park in northern New York in the United States. The word Sacandaga means "Land of the Waving Grass" in the local native language. The lake is located in the northern parts of Fulton County and Saratoga County near the south border of the Adirondack Park. A small part of it also extends northward into southern Hamilton County. The broader, south end of the lake is northeast of the City of Johnstown and the City of Gloversville. Great Sacandaga Lake is a reservoir. The original lake was greatly enlarged by a dam on the Sacandaga River at the northeast end of the lake.