The U.S. Department of Transportation's Federal Highway Administration has released a new report on the nation's busiest interstates showing people drove more than 84.7 billion miles on California highways in 2011, more than 900 times the distance from the Earth to the Sun, making the Golden State's highways the nation's busiest.

Overall, vehicles traveled 2.95 trillion miles on U.S. roads in 2011, the eighth-highest level ever recorded, and nearly double the amount traveled in 1980.

Photo: Evan Lockridge

Photo: Evan Lockridge

Traffic volume data from 2011, the most recent year available, show that the I-5 in California was the nation's busiest interstate, with 21.4 billion miles traveled that year. California's neighboring I-10 and I-110 followed as the second and third busiest, respectively. Los Angeles' section of I-405 serves an estimated 379,000 vehicles per day, making it the busiest interstate in any American city.

Texas came in second, with people driving more than 55.7 billion miles on its interstates, followed by Florida at 34.7 billion miles and Ohio at 31.4 billion miles.

Rounding out the top ten are:

  • Illinois, 31.033 billion miles
  • Georgia, 28.467 billion miles
  • Virginia, 24.062 billion miles
  • Pennsylvania, 23.662 billion miles
  • North Carolina, 21.241 billion miles
  • Michigan, 20.707 billion miles

The FHWA uses its Highway Performance Monitoring System to compute miles-traveled data for all interstates and highways. These data are based on thousands of automatic traffic recorders operated round-the-clock by state departments of transportation.

To see a complete list of the data, available by state and interstate, visit the FHWA's "U.S. Interstate Traffic Volume Analysis" at