Photo courtesy of David Herman (taken July 2007)
Missouri 221 was designated in 2007 to provide a direct route between US 67 in Farmington and Missouri 21 in Iron County at Pilot Knob. This photo shows the advance exit sign for Missouri 221 on US 67 in Farmington. It also indicates the highway's former designation as Route W in St. Francois County. The highway continues as Route W into central Farmington.
It's fairly obvious that the Missouri 221 shield was retrofitted onto the sign, giving it and the Route W marker an off-center appearance.