 Travel Tips with Peter Greenberg brought to you by Viking. 2024 may be another summer of the Great American Road Trip, but traffic is already worse in major U.S. cities. It may be because more and more Americans are living further from downtown areas and their offices. According to a study by Stanford University, between 2021 and 2023, the 56th largest metropolitan areas in the U.S. lost nearly 2 million people.