Indiana State Road 45 is a two lane highway that runs north/south through Bloomington. It originally extended from the southern border of Indiana down near Rockport and Evansville and goes until it reaches its end at SR 135 north east of Bloomington. Its southern terminus is now at US 231 near NSA Crane. While traveling through north east Bloomington, it is known as The Bypass.
After leaving Bloomington on the east, State Road 45 travels northeast past University Elementary and Mt. Gilead Christian Church before turning north to New Unionville. At the intersection of Bethel Lane it turns northeast again to pass through Unionville, just south of Lake Lemon. A CSX rail line parallels the highway from Bloomington to Danny Smith Memorial Park, before turning slightly northward, but rejoins the highway in the town of Trevlac.