Hydroplane Racing Action on Grand Lake St. Marys. Free admission. A weekend with something for everyone. Great Competition on the water at more than 100 miles an hour. More than a mile of spectator area. Food, beverages and amusements for the kids at lake side. Hot laps at 9 am and racing begins at noon both days. Last year more than 75 boats from with racers from the US, Canada and New Zealand competed for "The Cup".