Grand Lake St. Marys


Grand Lake St. Marys

Town(s): Celina OH, St. Marys OH

Size: 13500 acres
Average Depth: 6 feet
Maximum Depth: 16 feet

Boating Allowed: Kayaks, Canoes, Sail Boats, Electric Motor Boats, Power Boats, Jet-skis
Boating Comments: No HP Limit
Swimming: Swimming Allowed, Some Restrictions

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Grand Lake St Marys – was at one time the largest man-made lake in the world, but is still the largest inland lake in Ohio and is one of the oldest parks in the state. Completed in 1845 the lake was at one time surrounded by rich forestry, but today the area is known for vast farmland. At one time the lake was the site of the first offshore oil drilling in the world and until 1913 was a large oil producer. After it was made a state park in 1945 the lake has since become one of the country’s largest migration routes for several dozen types of birds including waterfowl and bald eagles. It is a vast area located 1.5 hours from Columbus and 1 hour from Fort Wayne Indiana.

Lake / Beaches / Marina – The lake is the largest inland lake in Ohio at 13,500 acres with 52 miles of shoreline. The lake only averages about 6 to 7 feet and reaches a maximum depth of 16 feet, however there are no horsepower or size restrictions on boats. The lake has 4 public beach areas for swimming as well as several more boat-swim areas around the lake. There are also 3 full service marinas that handle winterization, fuel and repair services. The park is also known to be a great fishing site full of bass, crappie, and catfish.

Offshore Amenities – The state park has 4 public picnic shelters for use along with an additional 9 picnic areas. There are also approx. 190 campsites available to the public. There is also a dog park called Fur-Ever Friends Dog Park as well as a miniature golf course. If that’s enough to do there are also playgrounds with basketball and volleyball courts! The lake also allows hunting in certain areas and is popular with duck hunters are there are 70 duck blinds available for use through a lottery system.

Nearby Activities – If hiking is your thing Grand Lake St Marys is right next to the Miami-Erie Trail, a 47 mile portion of the state-wide Buckeye Trail. It passes with 1.5 miles of the lake and ends at Delphos OH, 22 miles from the park. Lake Loramie State Park is also nearby and offers swimming, fishing, boating and camping opportunities. And if you want learn some history the Neil Armstrong Air and Space Museum, Neil Armstrong’s boy hood home, is located just within driving distance! 



Water Quality: Town/State Monitoring
Vegetation Growth: Unknown
Non-native Species:

Fish Species: Saugeye, Crappie, Largemouth Bass, Yellow Perch, Channel Catfish, Sunfish, Bluegill, Walleye

Boat Access: Access for Power and Non-power Boats
Ramp Comments: There are 8 public boat launces.
Parking Spaces: More than 40

Shoreline Development: 75-100%