For several years, an increase in bicycle routes has been observed in France and is accompanied by a significant number of deaths and injuries. Financed by the DSR (Road Safety Department), the COFACY project aims to describe profiles, uses and behaviours of cyclists and to identify the risky situations they encountered and their determinants. This project was prompted by a joint evolution of cycling mobility and data accidents. A naturalistic study was conducted in France in the regions of Ile de France (April to June 2022) and Auvergne-Rhône-Alpes (September to November 2022). A total of 78 volunteer cyclists were monitored for 4 weeks with a camera attached to the helmet. A logbook was completed after each route and weekly self-confrontation interviews were carried out to detail and review their critical situations. A particular attention was paid to the occurrence and environment of the situations (urban or rural areas). Cyclists completed 2152 routes and reported 779 risky situations. Results showed that the exposure to risky situations was twice as high in urban areas (1 situation every 80 min) than in rural areas (1 situation every 160 min). The main scenarios encountered were: “Non-compliance with lateral distances”, “Presence of an obstacle” and “Refusal of priority with signs” in both environments. Cars were the road users involved in the majority of situations both in urban and rural areas. These results will allow a better understanding of practice, uses and dangers encountered by cyclists according to the environment in order to direct further public decisions.