Lake Nipissing, 831 square km, at elevation 196 m,is the fifth-largest in Ontario excluding the great lakes, and is located 50 km northeast of Georgian Bay. Its name derives from an native language word meaning “little water.”

Lake Nipissing runs in an east-west direction to a length of 80 km. Because it parallels the prevailing winds, navigation is frequently treacherous. It is comparatively shallow (about 10 m in most places) and is consequently well aerated, which is conducive to healthy plant and fish life. Dozens of rivers and streams drain into Lake Nipissing, the largest being the Sturgeon River.

Historically its 2 most important outlets were the Mattawa River, which links it to the the Ottawa River system, and the French River, which issues from its southwest end, draining into Georgian Bay. Along this Ottawa-north Georgian Bay route travelled the early French explorers – the first being Étienne Brule in 1610 – tracing a path followed by fur traders for the next 200 years.

Permanent settlement around the lake dates from 1874 at Nipissing village in the southeast and from 1882 at North Bay when the CPR reached its NE shore. From the 1880s through to WWI Lake Nipissing was a major transportation route for settlers and lumbering, as steamships plied it regularly. Since then it has served mainly as a tourist and recreation waterway.