Recent Geomob Berlin speaker and avid cyclist Dave Whittingham discusses his project Kreuzungen, a service that allows users to upload their GPX tracks and find out which rivers they have crossed. The project started as a fun idea and has now gained popularity amongst Strava users. Dave highlights the importance of open data and open-source tools in making the project possible. Kreuzungen serves as an example of learning through experimentation and play in the geospatial community. Show notes on the Geomob website, where you can also learn more about Geomob events and sign up for our monthly newsletter.