Editing Interstate 170

{{short description|Auxiliary Interstate Highway in St. Louis County, Missouri, United States}}
{{For|the former route in Baltimore, Maryland|Interstate 170 (Maryland)}}
{{Use mdy dates|date=August 2021}}
{{Use American English|date=April 2022}}
{{Infobox road
| state = MO
| type = I
| route = 170
| map = {{maplink|frame=yes|plain=yes|frame-align=center|frame-width=290|frame-height=250|frame-lat=38.702|frame-long=-90.347|zoom=10|type=line|raw={{Wikipedia:Map data/Wikipedia KML/Interstate 170}}}}
| map_custom = yes
| map_notes = I-170 highlighted in red
| alternate_name = Inner Belt Expressway
| length_mi = 11.17
| length_ref = <ref name="fhwa">{{cite web |last=Starks |first=Edward |date=January 27, 2022 |title=Table 2: Auxiliary Routes of the Dwight D. Eisenhower National System of Interstate and Defense Highways |url=https://www.fhwa.dot.gov/planning/national_highway_system/interstate_highway_system/routefinder/table02.cfm |access-date=February 22, 2023 |work=FHWA Route Log and Finder List |publisher=[[Federal Highway Administration]]}}</ref>
| established = 1956{{cn|date=June 2019}}
| spur_type = I
| spur_of = 70
| direction_a = South
| terminus_a = {{jct|state=MO|I|64|US|40}} in [[Richmond Heights, Missouri|Richmond Heights]]
| junction = {{jct|state=MO|I|70}} in [[Berkeley, Missouri|Berkeley]]
| direction_b = North
| terminus_b = {{jct|state=MO|I|270}} in [[Hazelwood, Missouri|Hazelwood]]
| counties = [[St. Louis County, Missouri|St. Louis]]
| previous_type = US
| previous_route = 169
| next_type = MO
| next_route = 171
}}
'''Interstate&nbsp;170''' ('''I-170'''), also known as the '''Inner Belt Expressway''', is an {{convert|11.17|mi|km|adj=on}} north–south [[auxiliary Interstate Highway]] in [[Greater St. Louis]], [[Missouri]]. I-170 connects to [[Interstate 270 (Missouri–Illinois)|I-270]] at its northern terminus and [[Interstate 64 in Missouri|I-64]] at its southern terminus. I-170 crosses its parent, [[Interstate 70 in Missouri|I-70]], near [[St. Louis Lambert International Airport]].

==Route description==
{{section missing|date=April 2022}}

==History==
I-170 was originally intended to provide an [[inner beltway]] within I-270 through [[St. Louis County, Missouri|St. Louis County]] extending to [[Interstate 55 in Missouri|I-55]] in the southern part of the county, commonly called South County;<ref>{{cite news |title = Hundreds of Homes Face Razing for New Highway |last = Sutin |first = Phil |last2 = Hopgood |first2 = Mei-Ling |date = January 9, 1997 |work = [[St. Louis Post-Dispatch]] }}</ref> however, the portion of the route south of I-64/[[U.S. Route 40 in Missouri|US Route&nbsp;40]] (US&nbsp;40) was canceled due to [[Highway revolt|local opposition]]. The portion of [[MetroLink (St. Louis)|MetroLink]]'s Cross County Extension south of I-64 runs roughly along the proposed alignment.<ref>{{cite news |title = Westfall Sours On Extension of Interstate 170 |last = Sutin |first = Phil |date = March 14, 1997 |work = [[St. Louis Post-Dispatch]] }}</ref>

The southern portion of I-170 was built using St. Louis County funds in the 1960s through a shallow valley. It was signed as Route&nbsp;725.

===Recent construction===
The southern two interchanges on I-170 (at I-64/US&nbsp;40 and Galleria Parkway) were reconstructed as part of the first phase of the New I-64 project. Most notably, the new interchange includes direct access to I-170 from eastbound I-64; however, access to [[Saint Louis Galleria|Galleria Parkway]] from northbound I-170 was eliminated. Eager Road access to and from I-170 was also revised in the New I-64 project.<ref name="I-64">{{cite web |url = http://www.thenewi64.org/ProjectOverview.do |title = Project Overview |access-date = May 28, 2007 |work = The New I-64 |publisher = [[Missouri Department of Transportation]] |archive-url = https://web.archive.org/web/20070504060100/http://www.thenewi64.org/ProjectOverview.do |archive-date = May 4, 2007 |url-status = dead }}</ref>
==Southern extension==
Proposals have been made to extend I-170 south beyond its termination at [[Interstate 64 in Missouri|I-64]]/[[U.S. Route 40 in Missouri|US&nbsp;40]], and so connect to [[Interstate 55 in Missouri|I-55]], [[Interstate 270 (Missouri–Illinois)|I-270]], and [[Interstate 44 in Missouri|I-44]], and to towns such as [[Richmond Heights, Missouri|Richmond Heights]], [[Brentwood, Missouri|Brentwood]], [[Maplewood, Missouri|Maplewood]], and [[Marlborough, Missouri|Marlbourough]]. These towns currently lack direct access to the Interstates, [[St. Louis Lambert International Airport]], South County, and to each other. Many commuters travel on slower surface streets, such as Hanley Road or River Des Peres Boulevard, raising traffic in [[Shrewsbury, Missouri|Shrewsbury]] and other residential towns.<ref>{{Cite news |url = http://www.stltoday.com/news/local/metro/linking-south-county-clayton-studied/article_2bc4cfcb-f84d-5af0-ae05-c705a7a69832.html |title = Linking South County, Clayton studied |first = Ken |last = Leiser |work = St. Louis Post-Dispatch |access-date = January 19, 2018 |language = en |url-access = subscription }}</ref> These proposals had been postponed due to lack of funding.<ref>{{Cite news |url = http://fox2now.com/2013/05/14/south-county-connector-1st-phase-of-170-south-extension/ |title = South County Connector: 1st Phase of 170 South Extension? |date = May 14, 2013 |work = FOX2now.com |access-date = January 14, 2018 |language = en-US }}</ref>

==Exit list==
{{jcttop|exit|state=MO|county=St. Louis|length_ref=<ref name="modot">{{MoDOT Flex |access-date=March 18, 2015}}</ref>}}
{{MOint|exit
|location=Richmond Heights
|lspan=2
|mile=0.00
|exit=1
|road={{jct|state=MO|I|64|US|40|LCT|city1=Wentzville|city2=St. Louis}}
|notes=Signed as exits 1A (east) and 1B (west)}}
{{MOint|exit
|mile=0.438
|exit=1C
|type=incomplete
|road=Brentwood Boulevard north&nbsp;/ Eager Road
|notes=Southbound exit and northbound entrance}}
{{MOint|exit
|location=Clayton
|lspan=2
|mile=0.809
|exit=1D
|type=incomplete
|road=Brentwood Boulevard south
|notes=Southbound exit and northbound entrance (via Galleria Parkway)}}
{{MOint|exit
|mile=1.170
|exit=1E
|road=Forest Park Parkway east
|notes=Western terminus of the Forest Park Parkway}}
{{MOint|exit
|location=Ladue
|mile=1.611
|exit=1F
|road=Ladue Road
|notes=}}
{{MOint|exit
|location=University City
|mile=2.374
|exit=2
|road=Delmar Boulevard
|notes=}}
{{MOint|exit
|location=Olivette
|mile=3.336
|exit=3
|road={{jct|state=MO|MO|340|name1=Olive Boulevard}}
|notes=}}
{{MOint|exit
|location=Overland
|mile=4.325
|exit=4
|road={{jct|state=MO|Supp|D|name1=Page Avenue}}
|notes=}}
{{MOint|exit
|location=St. John
|mile=5.865
|exit=5
|road={{jct|state=MO|MO|180|name1=St. Charles Rock Road}}
|notes=}}
{{MOint|exit
|location=Bel-Ridge
|mile=7.027
|exit=6
|road={{jct|state=MO|MO|115|name1=Natural Bridge Road|location1=[[Lambert–St. Louis International Airport|Cargo City]]}}
|notes=Access to the [[University of Missouri-St. Louis]]}}
{{MOint|exit
|location=Berkeley
|lspan=6
|mile=7.654
|exit=7
|road={{Jct|state=MO|I|70|city1=St. Louis|city2=Kansas City}}
|notes=Signed as exit 7A (east) and 7B (west); exit 235}}
{{MOint|exit
|type=incomplete
|mile=7.771
|exit=7C
|road={{jct|extra=airport}} [[Lambert–St. Louis International Airport]]
|notes=Southbound exit is via exit 7B
}}
{{MOint|exit
|mile=8.577
|exit=8
|type=incomplete
|road=Scudder Road&nbsp;/ North Hanley Road
|notes=No northbound entrance}}
{{MOint|exit
|mile=9.167
|exit=9A
|road=Airport Road&nbsp;– [[Lambert–St. Louis International Airport|Cargo City]]
|notes=}}
{{MOint|exit
|type=incomplete
|mile=9.236
|exit=9B
|road=[[Boeing]]
|notes=Northbound exit and southbound entrance}}
{{MOint|exit
|type=incomplete
|mile=9.780
|exit=9C
|road=North Hanley Road
|notes=Northbound exit and southbound entrance}}
{{MOint|exit
|location=Hazelwood
|mile=10.894
|mile2=11.255
|exit=10
|road={{jct|state=MO|I|270|city1=Kansas City|location2=[[Chicago]]}}
|notes=Signed as exits 10A (west) and 10B (east)}}
{{Jctbtm|exit|keys = incomplete}}

==References==
{{reflist}}

==External links==
{{commons category|Interstate 170 (Missouri)}}
{{AttachedKML|display=title,inline}}
* [http://www.kurumi.com/roads/3di/i170.html#170mo Kurumi.com: Interstate 170]

{{3di|70}}

[[Category:Interstate 70|1]]
[[Category:Interstate Highways in Missouri|70-1]]
[[Category:Auxiliary Interstate Highways|70-1]]
[[Category:Transportation in St. Louis County, Missouri]]