Interstate 64 in Missouri

By | October 18, 2022


Get started Wentzville
End St Louis
Length 41 mi
Length 66 km
  • 1 → Kansas City
  • 2 Lake St. Louis
  • 4 → Maryland Heights
  • 6 O’Fallon
  • 9 Route K
  • 10 St. Charles
  • 11 Weldon Spring
  • 14 Chesterfield Airport Road
  • 16 Long Road
  • 17 Boone’s Crossing
  • Daniel Boone Bridge
  • 19 Olive Boulevard
  • 20 Chesterfield Parkway
  • 21 Timberlake Manor Parkway
  • 22 Woods Mill Road
  • 23 Maryville Center Road
  • 24 Mason Road
  • 25 → St. Louis Beltway
  • 26 Ballas Road
  • 27 Frontenac
  • 28 Lindbergh Boulevard
  • 30 McKnight Road
  • 31 → St. Louis Airport
  • 33 Bellevue Avenue
  • 34 Hampton Avenue
  • 36 Kingshighway Boulevard
  • 37 Grand Boulevard
  • 38A-D Jefferson Avenue
  • 39A-C Busch Stadium
  • 40A-B Downtown St. Louis
  • 40C → Kansas City / Memphis


Interstate 64 or I -64 is an Interstate Highway in the U.S. state of Missouri. I-64 forms an east-west route through the east of the state, located entirely in the St. Louis metropolitan area. The highway runs from the western suburb of Wentzville to the Poplar Street Bridge over the Mississippi River in St. Louis. I-64 is 66 kilometers long in Missouri.

  • ElectronicsMatter: State facts of Missouri, covering history, geography, demography, economics, politics, and administrative division of Missouri.

Travel directions

I-64 at Downtown St. Louis.

I-64 and the Poplar Street Bridge over the Mississippi River.

I-64 begins at Wentzville at an interchange with I-70, which also connects US 61 from Hannibal. I-64 has 2×2 lanes here and runs through the westernmost suburbs of St. Louis. After a few miles, a cloverleaf joins State Route 364, an alternate freeway to St. Louis. I-64 runs in a southeasterly direction and more or less forms the boundary between the western suburbs and the wooded hill country west of the conurbation.

From Weldon Spring, I-64 becomes busier and then has 2×4 lanes. One then crosses the Missouri River, after which the highway leads past an elongated business park with huge strip malls in the suburb of Chesterfield. I-64 has 2×3 lanes here. From the junction with State Route 141 there are again 2×4 lanes, then at Westwood a junction with the St. Louis ring road forms Interstate 270.

I-64 then leads through affluent suburbs closer to St. Louis, an area with a low density and much forest. This changes from Brentwood, where Interstate 170 joins, after which the 2×3 lane highway leads through the older suburbs and suburbs of St. Louis. In St. Louis, I-64 alternates between three or four lanes in each direction. Past Downtown St. Louis, I-64 crosses a double-deck overpass, then intersects with I-55. Via the Poplar Street Bridge, I-64 then crosses the Mississippi River, which also forms the border with the state of Illinois. Interstate 64 in Illinois then continues through East St. Louis toward Louisville.

  • Fun-wiki: Brief information of the state Missouri, covering basic history and geography as well as top cities of Missouri.


Long before I-64 was assigned to the current route, the highway existed as US 40, a major east-west axis through St. Louis. The highway was built in stages between 1930 and 1970, some overpasses predate it, such as the first Daniel Boone Bridge over the Missouri River that opened in 1935. The Poplar Street Bridge opened in 1967over the Mississippi River to traffic, and circa 1970 the double-deck overpass opened along Downtown St. Louis. In 1988, a second bridge over the Missouri was built in Chesterfield. Until 2009, there were still at-grade intersections on the westernmost portion of I-64 in Wentzville. Since then, the highway has been completely grade-separated. Also, the I-64 in the west of St. Louis was thoroughly modernized and widened between 2007 and 2009. Typical for Missouri, less common designs are also used here, such as a SPUI and roundabouts. On October 3, 2014, the converted cloverleaf junction with State Route 364 opened.

Express Highway in St. Louis

In St. Louis, the so-called ‘Express Highway’ was the predecessor of US 40 and I-64. This was the first highway-like road connection in the city. At the time, the city had more than 800,000 inhabitants. The original Express Highway was a 6-kilometer stretch of 2×2 lanes with grade separated intersections between Market Street near Downtown St. Louis and Clayton Road. On July 19, 1937, the first section opened between Vandeventer Avenue and Kingshighway Boulevard. The road was sunken and had a narrow profile. This was actually not a full-fledged highway. The speed limit was 30 mph until 1938, then 45 mph. The Express Highway was renamed the Red Feather Highway in 1948. In 1959, the Red Feather Highway was connected in the west to the new highway to the Daniel Boone Bridge west of St. Louis. Virtually nothing remains of the original ‘Express Highway’, the road was upgraded to a full-fledged freeway in the 1960s.

Opening history

Indicative data based on historical highway maps.

From Unpleasant Length Opening
exit 28 exit 36 13 km 00-00-1964*
exit 36 exit 37 2 km 00-00-1965
exit 37 exit 38 2 km 00-00-1966
Exit 40 state line 2 km 00-00-1967
exit 38 Exit 40 3 km 00-00-1970
Exit 25 exit 28 5 km 00-00-1972
Exit 10 Exit 25 24 km 00-00-1973
Exit 9 Exit 10 2 km 00-00-2004
Exit 2 Exit 4 3 km 00-00-2005
Exit 4 exit 6 3 km 00-00-2006
exit 6 Exit 10 6 km 00-00-2007
exit 0 Exit 2 3 km 00-00-2009

* Before 1964, this part was already a divided highway with some grade separated connections, exact date of freeway unknown.


Presumably in 1989, I-64 east of the Missouri River was widened. A second span of the Daniel Boone Bridge was also constructed at the time. A third span across the Missouri River at Chesterfield was constructed between early 2013 and June 29, 2015. The old bridge from 1935 was demolished after the new bridge opened. The project cost $125 million.

Some connections and nodes have also been added or reconstructed. I-64 originally had 2×3 lanes on a very tight cross section through Richmond Heights. The highway was widened to 2×4 lanes in 2008-2010. During the work, I-64 was completely closed for a long time and was completely demolished and reconstructed between I-170 and Clayton Road over 4.5 kilometers. The interchange with I-170 was then also converted to a half stack. In that period, Frontenac also completely demolished I-64 and reconstructed it with 2×4 lanes and new connections. Also in 2008-2009, two SPUIs were built east of it closer to St. Louis, with Hampton Avenue and Kingshighway Boulevard.

Traffic intensities

The intensities quickly rise from 36,000 to 91,000 from I-70 at the bridge over the Missouri River. The interchange with I-270 has 133,000 vehicles per day. Just before St. Louis, this peaks at 173,000 vehicles, before dropping to 90,000 vehicles along downtown. 99,000 vehicles cross the Mississippi River every day.

Lane Configuration

From Unpleasant Lanes Comments
Exit 1 Exit 10 2×2 St Louis
Exit 10 Exit 14 3+4 St Louis
Exit 14 exit 28 2×3 St Louis
exit 28 exit 36 2×4 St Louis
exit 36 Exit 40 2×3 St Louis
Exit 40 Exit 41 2×2 St Louis
Exit 41 Exit 42 2×4 St Louis

Interstate 64 in Missouri