INSIDER
On this day: The first tri-color traffic signal was installed in Detroit in 1920
Read full article: On this day: The first tri-color traffic signal was installed in Detroit in 1920On this day in 1920, the way people drove was changed forever when a Detroit traffic cop installed a four-way, tri-color traffic signal on Woodward Avenue in Detroit.
Head-and-neck restraints and soft walls top list of NASCAR's biggest safety improvements
Read full article: Head-and-neck restraints and soft walls top list of NASCAR's biggest safety improvementsTo mark NASCAR’s 75th season, The Associated Press interviewed 12 key contributors to the industry on multiple topics.