Add Yahoo as a preferred source to see more of our stories on Google. An example of what variable speed limit signs look like above a highway in Washington. (Courtesy of the Washington State ...

The speed limit on Interstate 70 in the high country will now change based on driving conditions thanks to newly installed ...

Speed limits across Texas roads are about to get smarter. In an effort to make highways safer and more responsive to real-time conditions, state officials are beginning a wider rollout of variable ...

Modern cars stop shorter, handle better, and protect occupants far more effectively than the vehicles most speed limits were originally designed around ...