Missouri Route 370

Route 370
Route 370 highlighted in red
Route information
Maintained by MoDOT
Length	12.957 mi[1] (20.852 km)
Existed	1993–present
Major junctions
West end	I-70 in St. Peters
Major intersections	Route 94 in St. Charles Route 141 in Bridgeton
East end	I-270 in Bridgeton
Location
Country	United States
State	Missouri
Counties	St. Charles, St. Louis
Highway system
Missouri State Highway System Interstate US State Supplemental
← Route 367 → Route 371

Missouri Route 370 (Route 370) is a freeway that connects St. Louis County with St. Charles County via the Discovery Bridge over the Missouri River. The St. Charles County segment of the freeway is signed as the Patrick J. Bray Memorial Highway while in St. Louis County it is signed as the Officer Scott H. Armstrong Memorial Highway.

Route 370 begins in St. Peters at a Y-interchange at I-70 exit 224 east of Mid Rivers Mall Drive and proceeds northeast. It loops around Fountain Lakes Park and crosses Cole Creek before turning to a southeasterly direction. It then passes north of St. Charles and interchanges with Route 94 at exit 7 before crossing the Missouri River. It then forms a Parclo interchange as it interchanges with Route 141 at exit 9 north of Earth City as it continues east. The route ends in Bridgeton, forming another Y-interchange at exits 22A and 22B on I-270 west of Missouri Bottom Road.^[2]

Construction on Route 370 began in the early 1990s. It was built to replace the section of St. Charles Rock Road, then designated as Route 115, west of I-270.^{[citation needed]}

MoDOT applied for an interstate highway designation of Interstate 370, but AASHTO rejected this in favor of the designation of Interstate 870. MoDOT did not want this because I-870 was their intended designation for what is now Interstate 255.^[3]

On December 16, 1992, the first section of the highway opened allowing direct access to St. Charles at Route 94 from I-270. It replaced the crumbling Old St. Charles Bridge that carried Route 115 traffic. On April 1, 1993, the road was designated as Route 370. In 1993, the Great Flood of 1993 surrounded much of the highway which is built on top of an embankment. As the flood waters surrounded the highway, many of the new exits had been shut down because the roads it connected to were underwater. Despite the flood, construction resumed on the highway until it was completed in 1996.^{[citation needed]}

County	Location	mi[1]	km	Exit	Destinations	Notes
St. Charles	St. Peters	0.000– 0.615	0.000– 0.990	1	I-70 – St. Louis, Kansas City	Western terminus; signed as exits 1A (east) and 1B (west)
		1.277– 1.573	2.055– 2.531	1C	Salt River Road	Westbound exit and eastbound entrance
		2.687	4.324	2	Truman Boulevard / Lakeside Park Drive
	St. Charles	5.110	8.224	5	Elm Street / New Town Boulevard
		7.882	12.685	7	Route 94 / Lewis and Clark Trail (North 3rd Street)
Missouri River		8.454	13.605	Discovery Bridge
St. Louis	Bridgeton	9.363	15.068	9	Route 141 south (Earth City Expressway)	Northern terminus of Route 141
		11.632	18.720	11	St. Louis Mills Boulevard
		12.343	19.864	12A	I-270 north – Chicago, IL	Eastbound exit and westbound entrance
		12.596	20.271	12B	Missouri Bottom Road	Eastbound exit and westbound entrance
		12.957	20.852	12C	I-270 south – Memphis, TN	Eastern terminus
1.000 mi = 1.609 km; 1.000 km = 0.621 mi       Incomplete access

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