There were more than 231 million cars, trucks, and buses registered in the United States in 2003. A rise in fuel prices makes travel more expensive but doesn't mean empty roads. Here are the U.S. highways that had the most traffic in 2003.
1. Los Angeles, highway I-405: 382,000 vehicles per day
2. Atlanta, I-75: 365,240
3. Houston, U.S. 59: 338,510
4. Chicago, I-90: 330,067
5. Seattle, I-5: 301,061
Source: Federal Highway Administration