Tucked along the southern shore of Kimiwan Lake in northern Alberta, McLennan sits approximately 50 kilometres north of High Prairie on Highway 2. The community takes its name from John K. McLennan, who served as vice president of the Edmonton, Dunvegan and British Columbia Railway, and was previously known as Round Lake. The name Kimiwan itself comes from the Cree word for rain. Situated northwest of Winagami Lake, McLennan also provides convenient access to Winagami Lake Provincial Park, which lies roughly 29 kilometres to the southeast.
The town has earned an informal reputation as the Bird Capital of Canada, a distinction rooted in the remarkable concentration of shorebirds and waterfowl drawn to the area by its neighbouring lakes during migration seasons. McLennan also holds religious significance as the home of Cathédrale Saint-Jean-Baptiste, a cathedral dedicated to John the Baptist and constructed in 1947, which serves as the archiepiscopal see of the Metropolitan Roman Catholic Archdiocese of Grouard-McLennan. According to the 2021 federal census, the town had a population of 695 residents living across 255 of its 322 private dwellings, a modest decline of roughly 0.9 percent from the 701 residents recorded in 2016. The town covers a land area of 3.58 square kilometres, giving it a population density of approximately 194 people per square kilometre.