Lake Käsmu
Käsmu järv (Estonian)
Lake Käsmu
Location	Eru, Lääne-Viru County, Estonia
Coordinates	59°35′N 25°53′E / 59.583°N 25.883°E / 59.583; 25.883
Basin countries	Estonia
Max. length	1,120 meters (3,670 ft)
Max. width	560 meters (1,840 ft)
Surface area	48.5 hectares (120 acres)
Average depth	1.9 meters (6 ft 3 in)
Max. depth	3.0 meters (9.8 ft)
Water volume	769,000 cubic meters (27,200,000 cu ft)
Surface elevation	3.9 meters (13 ft)

Lake Käsmu (Estonian: Käsmu järv) is a lake in Estonia. It is located in the villages of Eru and Käsmu in Haljala Parish, Lääne-Viru County. Lake Käsmu is located on the southern edge of the Käsmu Peninsula in northern Estonia.

The lake has an area of 48.5 hectares (120 acres). The lake has an average depth of 1.9 meters (6 ft 3 in) and a maximum depth of 3.0 meters (9.8 ft). It is 1,120 meters (3,670 ft) long, and its shoreline measures 3,020 meters (9,910 ft). It has a volume of 769,000 cubic meters (27,200,000 cu ft).^[1] It has diverse vegetation in terms of the number of species: there are 22 types of macrophytes.

• List of lakes of Estonia