Lake St. Clair is a large, shallow basin (20 to 23 miles wide) between two rivers. Water from the St. Clair River flows into the lake through a large delta formation in its northeast corner; the outflow goes down the Detroit River to Lake Erie. Lake St. Clair and its rivers are an important link between the lower and upper Great Lakes. Commercial ships follow a well-defined channel across the lake; they do not stop on the lake itself due top the lack of commercial ports. All the facilities around Lake St. Clair are designed for pleasure boats.

The lake has 160 miles of shoreline with several popular beaches. The 13 individual Metroparks that comprise the Huron-Clinton Metroparks offer access to over 1 mile of shoreline, a 1,600-foot boardwalk and eight boat ramps. Lake St. Clair Metropark is located along two intersecting migratory bird routes making it one of the top birding sites in Michigan. See an interactive map of things to do at Tour Lake St. Clair.