New York, San Francisco, Boston, and Washington, D.C. are the U.S. cities with the Best Mass Transit (Walking) Scores. This means that these cities are best suited to take people where they need to go using subways, bikes, busses, trains and other means of public transportation so that they don’t have to use their cars. This ranking factors accessibility, convenience, pedestrian friendliness, and the walkability of any address.

A good Mass Transit Score is great for the planet because, according to the EPA, motor vehicles collectively cause 75 percent of carbon monoxide pollution in the United States. By taking public transit whenever we can we can help to reduce our cities' carbon footprint and improve their Mass Transit Score.