Heat maps can be a tool for planning tours since they show routes most often traveled by other cyclists. A Strava personal heat map can also display personal data. I just generated one for all of my rides since 2012. You can see my rides in Quebec and upstate New York as well as favorite rides on the Erie Canal, Great Allegheny Passage, and Chesapeake and Ohio Canal. The rides that I do the most often are my local training rides shown in red.