Interstate 470 Colorado
Colorado 470 (C-470) follows the planned loop of Interstate 470 around the Denver metropolitan area south from I-70 at Golden and east to Littleton, Centennial and I-25 in Lone Tree. The commuter freeway serves an array of suburban development and Chatfield State Park.
C-470 Express Lanes
Started in 2016, construction underway through 2020 expands 12.5 miles of C-470 east from SH 121 (Wadsworth Boulevard) at Ken Caryl to Interstate 25 at Lone Tree. The $276 million project adds two managed lanes westbound from I-25 to Colorado Boulevard, and a single express lane from Colorado Boulevard to SH 121. One express lane is also being added eastbound from Wadsworth Boulevard to I-25. Work also adds auxiliary lanes, improves the ramp geometry at several interchanges and adds ramp metering where needed. Bid opening for the project took place on March 30, 2016.
C-470, which forms the southwestern quadrant of the Denver Beltway system, was adopted in 1969 by the Denver Metropolitan Area Transportation Study. Interstate 470 was added to the Interstate Highway System under the Federal Highway Act in December 1968.1 The route went through various studies through 1972, when the final environmental impact statement was released and submitted to the Federal Highway Administration (FHWA).
As was the case with several Interstate Highways studied in the early 1970s, the environmental impact statement brought controversy. Governor Dick Lamm, who was elected on a platform that included the elimination of Interstate 470 from Denver metropolitan area transportation plans, created the Interstate 470 Ad Hoc Commission. The commission studied the route and conducted public sessions. In December 1976, the commission recommended that I-470 should be withdrawn from the Interstate Highway System and an at-grade parkway (Centennial Parkway) be constructed in its place.1 Shortly thereafter, the Colorado Department of Highways concurred with the findings of the commission. On June 23, 1977, the FHWA approved eliminating Interstate 470.1
East End – Lone Tree, CO
West End – Golden, CO
Mileage – 28.162*
Cities – Golden, Lakewood, Littleton, Centennial, Lone Tree
- Junctions –
Source: * – 26.195 miles for Route 470A and 1.212 miles for Route 470W.
Colorado Department of Transportation Straight Line Diagram Tool
One of the key points made by Colorado Governor Dick Lamm in opposition to Interstate 470 was that the freeway would be the catalyst for suburban sprawl. Despite being built with just four lanes, Centennial Parkway ultimately fueled the suburban boon in Jefferson County and Lakewood.
Funds previously allocated for I-470 were earmarked not only to the Centennial Parkway corridor, but also to improvements on U.S. 85 (Santa Fe Drive) and other transportation improvements throughout the region. Construction got underway for Centennial Parkway in 1982, as Colorado 470. Design changes made by that time included interchanges in place of signalized intersections.
Referred to as C-470, Centennial Parkway opened in stages with the last section completed in October 1990. While Colorado 470 is a freeway, there are right in right out (RIRO) connections along westbound at Colorado 75 (Columbine Hills) and Hampden Avenue (Bear Creek Lake Park).
Starting in the 1990s and continuing through the 2000s, the Denver Beltway was extended east to Aurora and north to Broomfield as a toll road via Extension 470 (“E-470”) and the Northwest Parkway. These sections were never considered for inclusion in Interstate 470.
East End – Lone Tree, Colorado
West End – Golden, Colorado
Throwback – west at
- The Story of I-470, C-470, E-470, W-470, and the Northwest Parkway (Matthew Salek).
Page updated February 3, 2020.