Cass Lake is on the main branch of the Clinton River.

[3] Cass Lake is the largest and deepest lake in Oakland County, and is in the northern Metro Detroit region of southeastern Michigan.

[5] Cass Lake covers 1,280 acres (520 ha) and has a maximum depth of 123 feet (37 m).

It is a popular public lake in the Metro Detroit region.

The lake is home to the Pontiac Yacht Club.