Many U.S. West Coast cities are sandwiched by the Pacific Ocean and mountains to the east, squeezing traffic along a few big interstates that slow down at rush hour. And escaping downtown Seattle or San Francisco might require crossing a bridge. Traffic patterns also reflect a city’s activity, Brozen said. At 10 p.m. in Los Angeles, people might be cruising down Sunset Boulevard, making the streets busier than they would be in a sleepier town. In that way, traffic is an expression of a thriving local economy.
There are huge sections of the country accessible in an hour from the downtowns of most U.S. Western cities. That’s partly due to the relative lack of lakes, oceans, and mountains. But commuting patterns are also car-centric, with workers spread throughout the suburbs surrounding the city. These areas are growing fast. Austin’s population, for example, grew about 20 percent between 2010 and 2016. That means there are more cars on the streets, but it also means more roads are built as people commute from farther away. Plus, cities in the West don’t always have the same public policy restrictions around development as older cities in the East and Midwest, Lomax said.
Chicago has some of the worst traffic in the United States – it’s similar to older cities on the East Coast that weren’t built for cars. But the area accessible from other Midwestern downtowns hardly changes during the afternoon rush hour. That’s partly because Midwestern cities are growing more slowly than cities farther west, putting their roads and highways under less pressure.
Florida’s huge coastal cities are among the most difficult to escape at rush hour. Access to Miami, for example, is squeezed into an elongated slug-like shape by the Everglades to the west and the Atlantic Ocean to the east. Traffic isn’t confined to the coast, however. Despite being landlocked, Atlanta turns into a parking lot for cars traveling north each afternoon. If you want to make a quick escape, heading south is your best bet.
Because many U.S. East Coast cities developed well before the invention of the automobile, they weren’t designed for cars in the first place. That, along with the density of homes and businesses in the oldest part of the country, is evident in the congestion that develops at rush hour. While New York has a well-developed subway system (despite its recent trouble) it’s the hardest city to escape by car. No matter what time you leave, you can’t make it much farther than 30 miles from Manhattan in an hour.
