The August 22–25, 1878, convention of the New York Freethinkers’ Association (despite its name, a national conference) was held mostly in this park and partly in the Freer Opera House, about 500 feet to the west. Outdoor speeches and events were held at the park in a rented tent and in the open air. Convention attendance at this park ranged as high as 3,000 persons. Here woman’s rights (nineteenth-century practice was to use the singular, woman's; later practice was to use the plural, women's) and freethought activist Matilda Joslyn Gage delivered her first freethought address, whose contents formed the basis of her later book Woman, Church, and State. This park is the site where freethought journalist D. M. Bennett was arrested, along with two other freethinkers, on Saturday, August 24, for selling a controversial marriage-reform and birth control tract, Cupid’s Yokes by Ezra Heywood. This arrest led indirectly to a celebrated obscenity case involving decency crusader Anthony Comstock, agnostic orator Robert G. Ingersoll, President Rutherford B. Hayes, and others, which established the Hicklin standard, the repressive legal definition of obscenity that prevailed in U.S. law until 1957.
Though the New York State Freethinkers Association convened again in Watkins on August 23–27, 1882, because of rainy weather the park was not utilized, though seating and a tent had been set up. Most convention events took place in the Freer Opera House; a banquet honoring D. M. Bennett was held at the Glen Park Hotel.
The Association, then known as the Liberals and Freethinkers of Central and Western New York, held its first convention, or "Grove Meeting," on August 17–19, 1877, at the farm of freethinker James Madison Cosad in Huron, New York. (Some sources give the place name as Wolcott.)