Strava.com has made available a Heat Map of where their users collectively are generally going. It is available for both biking and running activities.
The following are screenshots of where South Central Alaskan’s bike per Strava.com’s data as of 05/17/2014.
As one would expect, the areas in red are places like Kincaid, Bird to Gird, the Coastal Trail, and the Lower Hillside; but there are some other interesting pieces of information on here, including perhaps someone’s partial Iditabike track? Either way an interesting find and kind of neat. Other fitness apps have similar information available but not so easy and pretty. This information, and information like it is a good community way for city planners (if they choose to use it) to see where biking is occurring and where to focus funding and improvements.
It is also a good reminder to keep in mind if you use any mobile apps as your cycling computer that your data may reveal your paths and patterns. Note: You cannot drill down on an individual user with this page.
Check it out yourself, I believe it is an aggregation of all recorded activity for an area, so this display is an aggregation as of 05/17/2014; not of the activity of 05/17/2014. Go to the link and expand the box for further information.