What makes a city fit for running? An accessible waterfront, the abundance of exercise trails and availability of uninterrupted paths are a good start.
Garmin, the company that creates GPS devices popular with runners, has released dozens of heat maps for the most-active cities in the United States -- and it shows where runners go to get their daily workout.
The GPS marker's Garmin Connect, a central storage area where runners and cyclist have logged more than 2.9 trillion miles, in March updated its services to allow users to see heat maps of cities, from New York to San Francisco.
"Runners and cyclists frequently ask us where they can find the most popular or safest places for their workouts," the company wrote in a blog releasing the new feature. "Besides being cool to look at, heat maps can help you find a new spot to work out, create a new course, see where you will be near other runners..."
Take a look at some of the most popular routes - outlined in colours, with red being the most active.
Have you run any of these routes?
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