This sign is for Columbia's second roundabout, completed in 2003, joining old Highway 63 via a short connecting road with the relocated Route AC on the southeast side of the city near the US 63 freeway. The new Route AC is known as Grindstone Parkway. The goal of the project was to divert traffic from busy and dangerous Nifong Boulevard.
The first roundabout in Columbia (and perhaps Missouri) was built just off I-70 at West Boulevard exit in the northwest part of the city in 2001.
This photo was taken March 11, 2003.