Grand Lake

Grand Lake St. Marys State Park is a public recreation area located on 13,500-acre Grand Lake in Mercer and Auglaize counties, Ohio. Grand Lake is the largest inland lake in Ohio in terms of area, but is shallow, with an average depth of only 5–7 feet.

Places of Interest

Highlights include Grand Lake St. Marys Seaplane Base and Grand Lake St. Marys Lighthouse.

Grand Lake St. Marys Seaplane Base

Aerodrome

Grand Lake St. Marys Seaplane Base is a public use seaplane base located five nautical miles southwest of the central business district of St. Marys, a city in Auglaize County, Ohio, United States.

Grand Lake St. Marys Lighthouse

Lighthouse

Photo: Nyttend, Public domain.

The Grand Lake St. Marys Lighthouse, also known as the "Northwoods Lighthouse", is a historic lighthouse on Grand Lake St. Marys, a reservoir in the far western part of the U.S. state of Ohio. Grand Lake St. Marys Lighthouse is situated 1½ miles northeast of Grand Lake.

Places in the Area

Nearby places include Montezuma and Celina.

Montezuma

Village

Photo: Nyttend, Public domain.

Montezuma is a village in Mercer County, Ohio, United States. The population was 152 at the 2020 census. Montezuma is situated 3½ miles southwest of Grand Lake.

Celina

Photo: Tysto, Public domain.

Celina is a city in West Central Ohio, serving as the county seat of Mercer County. Nestled along the shores of Grand Lake St. Marys, Ohio's largest inland lake, Celina offers a blend of outdoor recreation, arts, entertainment, and modern amenities, making it a welcoming destination for travelers.

Neptune

Hamlet

Neptune is an unincorporated community in Center Township, Mercer County, Ohio, United States. Neptune is situated 5 miles north of Grand Lake.

Grand Lake

Type: Reservoir
Also known as: “Celina Grand Reservoir”, “Grand Lake - Saint Marys”, “Grand Lake Saint Marys”, “Grand Reservoir”, “Lake Mercer”, “Lake Saint Mary’s”, “Lake Saint Marys”, “Mercer County Reservoir”, “Mercer Reservoir”, and “Saint Marys Reservoir”
Category: body of water
Location: Mercer, Ohio, Midwest, United States, North America
View on OpenStreetMap

Latitude

40.52667° or 40° 31′ 36″ north

Longitude

-84.50072° or 84° 30′ 3″ west

Elevation

869 feet (265 metres)

Open location code

86GQGFGX+MP

GeoNames ID

5156203

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Satellite Map

Discover Grand Lake from above in high-definition satellite imagery.

Places with the Same Name

Discover other places named “Grand Lake”.

Localities in the Area

Explore places such as Lees Landing and Club Island.

Notable Places Nearby

Highlights include Grand Lake St. Marys State Park and Safety Island.

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