Missouri Secondary State Route M is a east-west highway in Northern Jefferson County. It runs from U.S. Rt. 61/67, near Barnhart, to Missouri State Route 21, near Otto. MO Sec St Rt M passes through the following town in Jefferson County. Antonia MO Sec St Rt M is not multi-plexed in Jefferson County. MO Sec St Rt M intersects the following highways in Jefferson County. U.S. Rt. 61, near Barnhart. U.S. Rt. 67, near Barnhart. Interstate 55, near Barnhart. Missouri State Route 21, near Otto. Missouri Secondary State Route MM, near Otto.
A BGS on NB I-55. A BGS on NB I-55. A BGS on NB I-55. A BGS on SB I-55. A guide marker on the ramp from SB I-55. A guide marker in Barnhart. WB MO Sec St Rt M west of I-55. WB MO Sec St Rt M east of Moss Hollow Road. WB MO Sec St Rt M east of St. Luke's Church Road. A guide marker on WB MO Sec St Rt M. WB MO Sec St Rt M at MO St Rt 21.
