Interstate 5 in Oregon

Interstate 5 marker

Interstate 5

National Purple Heart Trail
Korean War Veterans Memorial Highway
Map
Map of Western Oregon with I-5 highlighted in red
Route information
Maintained by ODOT
Length308.14 mi[1] (495.90 km)
ExistedAugust 14, 1957[2][3]–present
HistoryCompleted in 1966
NHSEntire route
Major junctions
South end I-5 at California state line near Ashland
Major intersections
North end I-5 at Washington state line in Portland
Location
CountryUnited States
StateOregon
CountiesJackson, Josephine, Douglas, Lane, Linn, Marion, Clackamas, Washington, Multnomah
Highway system
OR 3 OR 6

Interstate 5 (I-5) in the U.S. state of Oregon is a major Interstate Highway that traverses the state from north to south. It travels to the west of the Cascade Mountains, connecting Portland to Salem, Eugene, Medford, and other major cities in the Willamette Valley and across the northern Siskiyou Mountains. The highway runs 308 miles (496 km) from the California state line near Ashland to the Washington state line in northern Portland, forming the central part of Interstate 5's route between Mexico and Canada.

I-5 was designated in 1957 and replaced U.S. Route 99 (US 99) for most of its length, itself preceded by the Pacific Highway and various wagon roads. The freeway incorporated early bypasses and expressways built for US 99 in the 1950s, including a new freeway route from Portland to Salem, and additional bypasses were built using federal funds. The last segment of I-5, on the Marquam Bridge in Portland, was opened in October 1966 and the whole highway was dedicated later that month. The freeway remains parallel or concurrent to Oregon Route 99 (OR 99) and its spur routes, running along former segments of US 99 that were bypassed by I-5, from Ashland to Portland.

Under Oregon's named route system, all of I-5 is designated as Pacific Highway No. 1. The Salem–Portland section was named the Baldock Freeway until 2022. The freeway also has three signed auxiliary routes that function as spurs and bypasses of major cities: I-105 in Eugene, I-205 in eastern Portland, I-405 in downtown Portland. Two additional auxiliary routes were planned in the early years of the Interstate system, but were shelved after local opposition.

  1. ^ "Table 1: Main Routes of the Dwight D. Eisenhower National System Of Interstate and Defense Highways as of December 31, 2017". Federal Highway Administration. December 31, 2017. Archived from the original on July 3, 2017. Retrieved June 22, 2018.
  2. ^ Official Route Numbering for the National System of Interstate and Defense Highways (Map). American Association of State Highway Officials, Public Roads Administration. August 14, 1957. Archived from the original on July 19, 2017. Retrieved April 14, 2013.
  3. ^ Weingroff, Richard F. (Summer 1996). "Federal-Aid Highway Act of 1956, Creating the Interstate System". Public Roads. Vol. 60, no. 1. Washington, D.C.: Federal Highway Administration. ISSN 0033-3735. Archived from the original on March 7, 2012. Retrieved April 14, 2013.