Glendalough was officially declared a state park with a celebration on Earth Day, April 22, 1992.

In 1905 the park was left to Valentine's children, John Alden and Miss Blanche, who later sold the land to Fred A. Everts.

On Earth Day in 1990, the land was donated to The Nature Conservancy by Cowles Media Company, and in 1992 the title was transferred to the State of Minnesota.

While that transfer took place in June,[3] celebrations of the park's anniversary are held around Earth Day.

As a result of this devastating incident, the park was closed to the public for a week to clean up debris left by the storm.

Less than ten months later, in 2005, Glendalough State Park was hit by another thunderstorm resulting in damage.

Within this restoration land, prairie plants such as Big Bluestem, Pasque Flower, and Pussy toe may be found.

Wildlife at Glendalough State Park consists of red-winged blackbirds, white-tailed deer, bald eagles, ospreys, turtles, Canada geese, wood ducks, pied-billed grebes, barred owls, red foxes, blue-winged teals, beavers, raccoons and snakes.