Interstate 270 Auxiliary route of the Interstate Highway System
Maintained by Illinois DOT and Missouri DOT
Length:	50.59 mi[1] (81.42 km)
Formed:	1956
CCW end:	I-55 / I-255 in Green Park, MO
Major junctions:	I-44 / US 50 / Route 366 in Sunset Hills, MO I-64 / US 40 / US 61 in Town and Country, MO I-70 in Bridgeton, MO I-170 in Hazelwood, MO I-255 / IL 255 near Pontoon Beach, IL
CW end:	I-55 / I-70 near Troy, IL
< IL 267 IL I-280 > < Route 269 MO Route 273 >

Interstate 270 (I-270) makes up a large portion of the outer belt freeway in the St. Louis, Missouri metropolitan area. The counterclockwise terminus of I-270 is at the junction with Interstate 55 in Mehlville, Missouri; the clockwise terminus of the freeway is at the junction with I-55 and I-70 north of Troy, Illinois. The entire stretch of I-270 is 50.59 miles (81.42 km).

Interstate 270 between Interstate 70 and Interstate 55 was formerly designated Interstate 244, a Western bypass of St. Louis, Missouri. It was originally proposed by Missouri as Interstate 144, but the road was a beltway (or part of one), so the AASHTO assigned it the number "244". By the late 1970s, the highway was integrated as a part of "270" for consistency.

[edit] History

During the Great Flood of 1993, the New Chain of Rocks Bridge carrying I-270 over the Mississippi River was the only bridge open from St. Louis to Keokuk, Iowa.

The last major construction project on I-270 occurred from 1995-1998. Both the Missouri Department of Transportation and the Illinois Department of Transportation upgraded I-270 to modern standards from Lilac Ave. to I-255.

On September 13, 1999, a fatal accident involving a tractor-trailer occurred in the westbound lanes of I-270^[2] in front of the now-defunct St. Thomas Aquinas-Mercy High School (now North County Christian School) in North St. Louis County. This accident sped up efforts that led to the I-170/270 interchange reconstruction that went from 2001 to 2004.

A major chemical spill from a FedEx truck between the Route 367 and Lilac exits on October 28, 2002 forced detours and lengthy delays.^[3]

There were plans to sign an eight mile (13 km) section of I-270 from Glen Carbon to Edwardsville as I-870. However, this idea was discarded.^[4]

In 2008 MODOT Implemented new Variable speed limits on I-270/255 with the normal limit being 60 mph (97 km/h). ^[5]

[edit] Future

IDOT wants to widen I-270 from Lilac to I-255 from four lanes to six, but no money is available at the current time.^[6] However, IDOT has announced that nearly $75 million has been programmed for replacement of the canal bridges between 2010 and 2014. ^[7]

[edit] Exit list

County	Location	Mile[8]	#	Destinations	Notes
St. Louis	Green Park	0.00		I-255 east  – Chicago	Continuation beyond I-55 / US 61 / US 67
		0.00	1C	US 61 / US 67 (Lemay Ferry Road)	Eastbound exit and westbound entrance
		0.00	1	I-55 – St. Louis, Memphis	Signed as exits 1A (south) and 1B (north)
		1.89	2	Route 21 (Tesson Ferry Road)
	Sunset Hills	3.64	3	Route 30 (Gravois Road)
		5.68- 5.98	5	I-44 / US 50 / Route 366 east – St. Louis, Tulsa	Signed as exits 5A (east) and 5B (west)
	Kirkwood	7.56	7	Big Bend Road	Southbound exit and northbound entrance
	Des Peres	8.45	8	Dougherty Ferry Road
		9.91	9	Route 100 (Manchester Road)
	Town and Country	12.43	12	I-64 / US 40 / US 61 – Wentzville, St. Louis
	Creve Coeur	13.58	13	Route AB (Ladue Road)
		14.73	14	Route 340 (Olive Boulevard)
	Maryland Heights	16.31	16A	Route D east (Page Avenue)
		16.66	16B	Route 364 west
		17.67	17	Dorsett Road
	Bridgeton	20.04	20	I-70 – Kansas City, St. Louis	Signed as exits 20A (east) and 20B (west)
		20.81	20C	Route 180 (St. Charles Rock Road) / Natural Bridge Road
		22.48	22	Route 370 west
		22.18	22	Missouri Bottom Road	Eastbound exit and westbound entrance
	Hazelwood	23.58	23	McDonnell Boulevard
		25.24	25	US 67 (Lindbergh Boulevard)	Signed as exits 25A (south) and 25B (north)
		26.31	26A	I-170 south – Clayton
		26.61	26B	North Hanley Road, Graham Road
	Florissant	27.57	27	Route N (New Florissant Road)
		28.10	28	Washington Street, Elizabeth Avenue
		29.59	29	West Florissant Avenue
		30.29	30	Route AC (New Halls Ferry Road)
		30.64	30A	Old Halls Ferry Road	Westbound exit and eastbound entrance
	Moline Acres	31.82	31	Route 367 – St. Louis, Alton	Signed as exits 31A (south) and 31B (north)
	Bellefontaine Neighbors	32.79	32	Bellefontaine Road
		33.77	33	Lilac Avenue
		34.88	34	Riverview Drive
New Chain of Rocks Bridge over the Mississippi River (state line)
Madison		2.73	3	IL 3 / Great River Rd. north / GRR spur south – Granite City, Alton	West end of GRR overlap; signed as exits 3A (south) and 3B (north)
			4	Old Alton Road
		4.39	4	IL 203 south – Granite City
		5.92	6	IL 111 / Great River Rd. south – Pontoon Beach, Wood River	East end of GRR overlap; signed as exits 6A (south) and 6B (north)
		7.16	7	I-255 south / IL 255 north  – Memphis, Wood River	Signed as exits 7A (south) and 7B (north) westbound
		9.13	9	IL 157 – Collinsville, Edwardsville
		11.87	12	IL 159 – Collinsville, Edwardsville
		14.57	15	I-55 / I-70 west – Chicago, St. Louis	Eastbound exit and westbound entrance; signed as exits 15A (south/west) and 15B (north)
		14.57		I-70 east  – Indianapolis	Continuation beyond I-55 / I-70 west

[edit] References

v • d • e Auxiliary routes of Interstate 70 Colorado: 270 • 470 (former) — Kansas: 470 — Missouri: 170 • 470 — Ohio: 270 • 670 — Maryland: 170 (former) • 270 • 270 Spur • 370 — Multi-state: 270 (IL-MO) • 470 (OH-WV) • 670 (KS-MO)