Missouri Route 21

Route 21 Business
Route 21 Business
Location	Hillsboro, Jefferson County

Route 21
Route 21
Tesson Ferry Road
Route information
	Maintained by MoDOT
Length	188 mi (303 km)
Existed	1922–present
Major junctions
South end	AR 115 at the Arkansas state line
	US 160 in Doniphan; US 60 near Van Buren; Route 72 in Centerville; Route 49 in Hogan; Route 32 in Caledonia; Route 47 in Mineral Point; Route M / Route MM in Barnhart; Route 141 in Paulina Hills; I-270 in Concord; US 50 / US 61 / US 67 in Concord;
North end	Route 30 in Affton
Location
Country	United States
State	Missouri
Counties	Ripley, Carter, Reynolds, Iron, Washington, Jefferson, St. Louis
Highway system
	Missouri State Highway System; Interstate; US; State; Supplemental;

Route 21 is a highway in eastern Missouri. Its northern terminus is at Route 30 in Affton. Its southern terminus is at the Arkansas state line (where it continues as Highway 115). In the St. Louis area, it is known as Tesson Ferry Road, which was named after the 19th century proprietor of the ferry across the Meramec River.

The section through northern Jefferson County, Missouri was considered dangerous. As a result, the road was rerouted and built to freeway standards. Construction to reroute the highway to just south of Hillsboro was completed on December 15, 2008 and Route 21 is currently freeway standard from Route 141 to Highway B. Plans to extend the freeway south to De Soto have been approved, but funds are lacking to complete this part of the project.^[1]

Route 21 from the Meramec River to Route B, along with Route M, make up the Jefferson County Scenic Byway.^[2]^[3]

Major intersections

County	Location	mi	km	Destinations	Notes
Ripley		0.000	0.000	AR 115 south – Pocahontas	Arkansas state line
		8.578	13.805	Route 142 west – Gatewood	Southern end of Route 142 overlap
		9.825	15.812	US 160 west – Alton	Southern end of US 160 overlap
	Doniphan	11.714	18.852	Route 142 east – Business District	Northern end of Route 142 overlap
		13.677	22.011	US 160 east – Poplar Bluff	Northern end of US 160 overlap
Carter		36.031	57.986	US 60 east – Poplar Bluff	Southern end of US 60 overlap
Carter		45.608	73.399	US 60 west / Route 34 begins – Van Buren	Northern end of US 60 overlap; Southern end of Route 34 overlap
Reynolds		48.959	78.792	Route 34 east – Clearwater Dam, Piedmont	Northern end of Route 34 overlap
	Ellington	65.112	104.788	Route 106 west – Owls Bend, Eminence, Business District
		77.088	124.061	Route 72 west – Bunker	Southern end of Route 72 overlap
		85.027	136.838	Route 49 north – Black, Oates	Southern end of Route 49 overlap
Iron		98.252	158.121	Route 49 south – Annapolis	Northern end of Route 49 overlap
	Arcadia	107.967	173.756	Route 72 east	Northern end of Route 72 overlap
	Pilot Knob	110.072	177.144	Route 221 north
		119.405	192.164	Route 32 west	Southern end of Route 32 overlap
Washington	Caledonia	123.672	199.031	Route 32 east – Bismarck	Northern end of Route 32 overlap
	Potosi	135.913	218.731	Route 8 – Potosi, Leadwood
	Old Mines	142.085	228.664	Route 47 south – Bonne Terre	Southern end of Route 47 overlap
		147.011	236.591	Route 47 north – Richwoods	Northern end of Route 47 overlap
	Washington State Park	149.523	240.634	Route 104 east
	Washington State Park	150.912	242.869	Route 104 west
Jefferson		161.379	259.714	Route 110 east
	Hillsboro	165.177	265.827	Route B begins / Business 21	Southern end of Route B overlap
		165.547	266.422	Route B north	Northern end of Route B overlap; southern end of freeway
	Hillsboro	167.854	270.135	Route A / Business 21
		169.236	272.359	Hayden Road
		172.575	277.733	Old Route 21 - Goldman
		175.162	281.896	Old Route 21 / Schenk Road
	Otto	177.733	286.034	Route MM / Route M – House Springs, Barnhart
		180.341	290.231	Old Route 21 - Shady Valley
		184.555	297.012	Old Route 21 - Meramec Heights	Southbound exit and northbound entrance
		185.469	298.483	Route 141 – Fenton, Arnold	Interchange; northern end of freeway
		185.864	299.119	Meramec Bottom Road
St. Louis	Concord	190.517	306.607	I-270 – Chicago, Memphis	I-270 exit 2
	Concord	191.717	308.539	US 50 / US 61 / US 67 (Lindbergh Boulevard)
	Affton	194.126	312.416	Route 30 (Gravois Road)
1.000 mi = 1.609 km; 1.000 km = 0.621 mi Incomplete access

Hillsboro Business Spur

Business 21 follows the old alignment of Route 21 through the city of Hillsboro. It begins at the intersection of Route 21 and Highway B on the southern edge of the city, and continues north to the intersection of Route A and Old Route 21, where it ends. Business 21 is the only way one can now reach Route BB, as the rerouting of Route 21 bypasses the road.