U.S. Route 20 in Iowa

U.S. Highway 20 marker
U.S. Highway 20
Map
US 20 highlighted in red
Route information
Maintained by Iowa DOT
Length300.270 mi[1] (483.238 km)
Existed1926–present
Major junctions
West end I-129 / US 20 / US 75 at South Sioux City, Neb.
Major intersections
East end US 20 at East Dubuque, Ill.
Location
CountryUnited States
StateIowa
Counties
Highway system
US 18 Iowa 21

U.S. Highway 20 (US 20) in Iowa is a major east–west artery which runs across the state, separating the northern third of Iowa from the southern two-thirds. It enters Iowa from Nebraska, concurrent with Interstate 129 (I-129) and US 75, crossing the Missouri River at Sioux City. US 20 runs in a more-or-less straight line across Iowa, paralleling 42° 27' N. It leaves Iowa in Dubuque by crossing the Mississippi River into Illinois. Since October 2018, US 20 is a four-lane divided highway for its entire length in Iowa.

  1. ^ Cite error: The named reference DOTGIS was invoked but never defined (see the help page).