Missouri State Route 109 is a north-south highway in Western St. Louis County. This runs from Interstate 44/U.S. Rt. 50 to near the Wildwood/Chesterfield City Limits. MO St Rt 109 passes through the folowing towns in St. Louis County. Eureka
Wildwood MO St Rt 109 is not multi-plexed in St. Louis County. MO St Rt 109 intersects the following highways in St. Louis County. Interstate 44, at Eureka. U.S. Rt. 50, at Eureka. Missouri Secondary State Route W, at Eureka. Missouri State Route 100, at Wildwood. Missouri Secondary State Route BA, at Wildwood. Missouri Secondary State Route BA, at Wildwood.
