In the United States, the major east-west Interstate highways are denominated by multiples of tens: I-10 goes from Los Angeles to Jacksonville, Fla. I-40 goes from Barstow, Calif., to Wilmington, N.C. I-80 goes from San Francisco to New York.
The north-south Interstates, meanwhile, are denominated with fives. I-5 goes from the U.S.-Mexico border, through San Diego, Los Angeles, Portland, Ore., and Seattle and ends at the U.S.-Canada border. I-15 goes from from San Diego to the Canadian border near Sweetgrass, Mont. And I-95 heads north from Miami all the way to northeast Maine.
Over the … Read more