It runs in north–south in south central Wisconsin from near Tennyson to near Lone Rock.

Starting at US 61/WIS 35 in Tennyson, WIS 133 begins to travel westward along with the Great River Road.

They then turn northward after leaving Cassville, passing through North Andover.

This time, the two routes run along WIS 35 before intersecting US 18 north of Patch Grove.

After going through elevated terrain, WIS 133 turns northeastward as it meets the south bank of the Wisconsin River.