Wisconsin State Route 21 runs east-west along Central Monroe County. It runs from Sparta to the Monroe/Juneau County Line, near Wyeville. WI St Rt 21 passes through the following towns in Monroe County. Sparta
Angelo Fort McCoy Tunnel City Wyeville WI St Rt 21 is not multi-plexed in Monroe County. WI St Rt 21 intersects the following highways in Monroe County. Wisconsin State Route 16, at Sparta. Wisconsin State Route 71, at Sparta. U.S. Rt. 12, near Tunnel City. Interstate 94, near Tunnel City. Wisconsin State Route 173, near Wyeville.
A set of guild markers on the ramp from WB I-90 to WI St Rt 16. A junction marker on WB WI St Rt 16/71. A junction marker on SB WI St Rt 27/EB WI St Rt 71.
