ST. LOUIS (First Alert 4) - Forest Park is marking its 150th birthday, celebrating a milestone that dates to the park’s opening to the people of St. Louis on June 24, 1876. “We’re excited. It’s a big birthday,” said Dominik Jansky, director of communications for Forest Park Forever, who noted the 1,326-acre park has long served as a gathering place for the region. Forest Park hosted the 1904 World’s Fair and the Summer Olympics, Jansky said.