What Makes Bike-Sharing Work? Insights from 43 Million Kilometers of European Cycling Data

Bike- and e-bike-sharing promise sustainable, equitable mobility - but what makes these systems successful? Despite hundreds of cities operating thousands of shared bikes, trip data is rarely public. To address this, we built a geospatial analysis pipeline that reconstructs trip data from publicly accessible system status feeds. Using this method, we gathered **43 million km** of bike-sharing trips across **268 European cities**. Combined with over **100 urban indicators** per city, our analyses reveal how infrastructure, climate, demographics, operations, and politics shape system performance. We uncover surprising insights - such as why some e-bike systems underperform despite strong demand - and highlight how cities can design smarter, fairer mobility. All data and code are open-source, with an interactive demo at [dataviz.nefton.de](https://dataviz.nefton.de/).