State Road 550 exists in two portions. The western section is completely within Knox County

Knox County, Indiana

As of the census of 2000, there were 39,256 people, 15,552 households, and 10,139 families residing in the county. The population density was 76 people per square mile . There were 17,305 housing units at an average density of 34 per square mile...

 and has a western terminus east of Emison

Emison, Indiana

Emison is an unincorporated town in Busseron Township, Knox County, Indiana. Its population was 154 at the 2010 census.-Geography:Emison is located at ....

 at U.S. Route 41

U.S. Route 41 in Indiana

In the U.S. state of Indiana, U.S. Route 41 is a north–south highway that is parallel to the Illinois state line. It enters the state south of Evansville. North of Evansville, it becomes a 4-Lane divided highway passing around Vincennes and traveling North to Terre Haute. In Terre Haute, it...

/U.S. Route 150 and runs southeasterly to the U.S. Route 50

U.S. Route 50 in Indiana

In the U.S. state of Indiana, U.S. Route 50 is a major east–west route. It enters Indiana from Illinois and leaves Indiana into Ohio.- Route description :...

/US 150 concurrency in Wheatland

Wheatland, Indiana

Wheatland is a town in Steen Township, Knox County, Indiana, United States. The population was 480 at the 2010 census.-History:Wheatland was founded in 1806. James D...

.

The eastern section terminates at both ends at US 150 in Martin County

Martin County, Indiana

As of the census of 2000, there were 10,369 people, 4,183 households, and 2,877 families residing in the county. The population density was 31 people per square mile . There were 4,729 housing units at an average density of 14 per square mile...

 between Loogootee

Loogootee, Indiana

-Demographics:As of the census of 2000, there were 2,741 people, 1,226 households, and 712 families residing in the city. The population density was 1,750.5 people per square mile . There were 1,337 housing units at an average density of 853.8 per square mile...

 and Lacy.

Western segment

The western segment of SR 550 begins at an intersection

Intersection (road)

An intersection is a road junction where two or more roads either meet or cross at grade . An intersection may be 3-way - a T junction or fork, 4-way - a crossroads, or 5-way or more...

 with US 41/US 150. SR 550 heads southeast towards Wheatland passing through an intersection with State Road 67

Indiana State Road 67

State Road 67 in the U.S. State of Indiana cuts a diagonal route from southwest to northeast across the state from the north side of Vincennes to Indianapolis to the Ohio state line, where it becomes State Route 29 east of Bryant.-Route description:...

 in Bruceville

Bruceville, Indiana

Bruceville is a town in Washington Township, Knox County, Indiana, United States. The population was 478 at the 2010 census.-Geography:Bruceville is located at ....

. SR 550 enters Wheatfield on the northwest side of town and heads towards its eastern terminus of this section at an intersection with US 50/US 150

Eastern segment

The eastern section of SR 550 begins in Loogootee, east of the US 50/US 150/U.S. Route 231 intersection. SR 550 heads southeast then turning east. The eastern terminus of SR 550 is at an intersection with US 150.

Major intersections

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