This is a lovely run combining a historic park and a section of the riverfront Mississippi Greenway. Jefferson Barracks Park ks 19th-century army outpost still in use, with numerous outbuildings set aside as historical exhibits. A loop of the park’s paths is ~2.5 miles. Then, run on a section of the Mississippi Greenway north for ~1.5 miles to the River City Casino. Nice river views on this paved multi-use path. So overall this is a ~5.3 mile route.
Longer Run: From the Casino, run briefly west on River City Casino Blvd. to connect to the River des Peres Greenway, a 9.3 mile multi-use path along the wide open green space that wraps around the River Des Peres as it winds its way to the Mississippi River.