Thumb Area Bottomland Preserve

Thumb Area Bottomland Preserve
Location within the state of Michigan
LocationLake Huron, Huron County, Michigan USA
Nearest cityPort Austin, Michigan
Coordinates44°01′24″N 82°46′16″W / 44.0232°N 82.771°W / 44.0232; -82.771
Area276 square miles (710 km2)
Governing bodyMichigan Department of Natural Resources

The Thumb Area Bottomland Preserve, also called the Thumb Area Underwater Preserve, is a preservation area in Lake Huron in the U.S. state of Michigan. It is 276 square miles (710 km2) in size and is located off Michigan's Thumb north of Detroit.