Lesser Slave Lake is a lake located in central Alberta, Canada, northwest of Edmonton. It is the second largest lake entirely within Alberta boundaries (and the largest easily accessible by vehicle), covering 1160 square km and measuring over 100 km long and 15 km at its widest point. Lesser Slave Lake averages 11.4 m in depth and is 20.5 m at its deepest. It drains eastwards into the Athabasca River by way of the Lesser Slave River.
The town of Slave Lake is located at the eastern tip of the lake, around the oultflow of Lesser Slave River. According to the town's website, the name Slave Lake originated with "an aboriginal nation derogatorily named 'Slavee' by several tribes of the invading Cree nation."
Due to its location, Lesser Slave Lake is popular with birders, being located on a major fly-way for migrating birds, most notably eagles and pelicans.
Nearby Lesser Slave Lake Provincial Park has lakeside camping facilities, located along sand beaches. Fishing is popular and legal. The entire north shore of the lake is protected, other reserves being Hilliard's Bay Provincial Park, Lesser Slave Lake Wildland and Grouard Trail Park Reserve.
There are a number of indian reserves established at the shores of the lake: