U.S. Federal Route 54 is one of the main highways across Audrain County. It is a four-lane highway from the Callaway-Audrain County Line to Mexico. The four-lane section runs north-south. From Mexico to near Martinsburg, it runs east-west. North of Martinsburg, to north of Laddonia, U.S. Rt. 54 runs north-south. U.S. Rt. 54 goes east-west from north of Laddonia to the Audrain/Ralls County Line. U.S. Rt. 54 passes through the following towns in Audrain County. Mexico
Laddonia
Farber
Vandalia
U.S. Rt. 54 is multi-plexed in Audrain County. Missouri State Route 19, from near Martinsburg to near Laddonia.
Branches of U.S. Rt. 54 in Callaway County. EB U.S. Rt. 54 at the Callaway/Audrain County. EB U.S. Rt. 54 south of Mexico. A BGS on EB BUSN U.S. Rt. 54/NB MO St Rt 15/WB MO St Rt 22. EB U.S. Rt. 54/NB MO St Rt 19 in Laddonia. A junction marker on NB MO Sec St Rt W.