In 1916, Dayton industrialists Charles Kettering and Edward Deeds purchased Daniel Eldridge Mead’s “Idylwild” estate and a larger adjacent tract to save the land from development and create a park for their companies. Triangle Park opened with a July 4, 1917, picnic for employees and their families. A few weeks later, on July 15, the site became the World War I recruitment site for nearly two hundred men enlisting as “Camp Triangle, Battery D, 1st Ohio Field Artillery.” The park was home to the company football team, the Dayton Triangles, and it was the site of the first NFL game in 1920. In 1941, Deeds and Kettering gave the park to the City of Dayton to ensure its continued recreational use forever as “a gathering place.”