These are Lake Athabasca, 7898 km², part of which is in the province of Saskatchewan, Lake Claire, 1436 km², and Lesser Slave Lake, 1168 km².
An Alberta sinn eng Hällewull vu Séien, déi dräi gréisst Séie sinn de Lake Athabasca (7.898 km²), Lake Claire (1.436 km²) an de Lesser Slave Lake (1.168 km²).