Brought to you buy Strava Labs. This is an incredibly large data set of places to bike and run South Florida but also just about anywhere in the world you can imagine. The data is very granular so once you drill down to a more specific place you will see even more detail.
What makes these maps interesting from a luxury real estate perspective is that great places to ride are usually great places to live. The Main tracks in South Florida take you to Key Biscayne, Coconut Grove, Ponce Davis, Coral Gables and Pinecrest. As you head further north-west closer to the Everglades, you see lots of Activity in the Weston, SouthWest Ranches, Davie area which have great parks and homes for many local professional athletes, etc.
At the time of this posting, the heat maps provided by Strava where getting hit pretty hard so a bit of patience might be in order but the results are really worth the wait.
If not at the link above in the first paragraph, you can also go to the Strava labs website where they have some other interesting GPS based mapping interactions. Click HERE for that page.
There is also below an embed of the Strava labs page you can try out as well. Just set your heat map options and then minimize the options screen to see the map. ENJOY!