The SAFER barrier at the Las Vegas Motor Speedway. The outer wall is hollow square steel tubing. The trapezoidal shapes are energy-absorbing foam.

"Soft walls" aren't really soft, but they are a lot softer than the conrete retaining walls they have replaced. SAFER (Steel And Foam Energy Reducing) barriers are one of the most significant safety advances in motorsports. They were developed as a joint effort between the Indy Racing League and NASCAR with the University of Nebraska's Midwest Roadside Safety Facility. The Director of the MWRSF and leader of the SAFER barrier development effort at the University of Nebraska, Dean Sicking, received the 2005 National Medal of Technology, which is the highest civilian honor the U.S. Government awards in the area of technology. The medal is awarded by the President of the United States and recognizes Dean's leadership not just in track safety, but in highway safety as a whole.