Sitting on the western edge of the city, Forest Park covers 1,400 acres, making it one of the largest urban parks in the country. The host of the 1904 World’s Fair, the park is home to some of the major city attractions including the Missouri History Museum, the St. Louis Zoo, St. Louis Science Center, St. Louis Art Museum, a series of small islands, and many biking and running trails. This perimeter run will take you by Jefferson Lake and the Missouri History Museum, and is only a handful of stops on the Metro Rail system from downtown.
Nice add-on option: ~1 mile west to the Washington University of St. Louis, and then another ~1 mile to downtown Clayton, along Forsythe Blvd. Also some pleasant suburban/residential running on side roads.