The Terwilliger curves, just south of Portland, Oregon, constitute the most dangerous section of US Highway Interstate-5. I-5 extends approximately 1,380 miles from Canada to Mexico, but this two-mile stretch of S-curves has the highest concentration of road accidents.
The problem is the curves are inadequately banked for highway speeds. Add poor visibility and slick road conditions and you have a formula for automotive disaster, with an average 28 reported accidents per month.
Since the Oregon Department of Transportation reduced the speed limit to 50 MPH and Portland Police stepped up patrols in 1995, the accident rate dropped considerably, reaching an average of 15 accidents per month in 1997.
To see what's happening on the Terwilliger curves right now, check out the web cam at: http://www.tripcheck.com/RoadCond/izone16.htm. Hover your pointer over the little camera icon along I-5 next to the words "Multnomah Blvd"; the title should read "Road Cam - I-5 @ Terwilliger". Click to view.
Source:ODOT news release http://www.odot.state.or.us/region1/f_news/news1204.htm