We designed a set of maps for, showing the explosive growth of the service since it started in 2008. The first visualization represents Airbnb’s top 50 markets.

The thickness of the lines corresponds to the relative volume of travels between each pair. Below that are maps of NYC and SF. Darker city blocks have less listings, brighter blocks have more. It's amazing to see how quickly some areas fill in as more and more people discover they can list their apartments—and to see which areas stay dark.