OBJECTIVES: The main objective was to estimate the nature, severity and medical care of severe trauma injuries following mountain activities as compared to severe trauma following traffic accident in a mountain area. STUDY DESIGN: We conducted a prospective comparative monocentric observational study at a University Hospital located in the northern Alps area, using the First national study database (French intensive care recorded in severe trauma). PATIENTS AND METHODS: Three hundred and thirty-seven patients were included during a 2-year-period from January 2005 to December 2006. Three hundred and thirty-seven patients, including 223 traffic accidents and 114 mountain accidents were included. The survey data was achieved with a standardized method on a period of 30 days after the accident, and recorded in a computerized file for optimal completeness. RESULTS: The study did not show higher severity or mortality rates in patients with mountain accidents. In both groups, we found a peak of mortality for young adults and similar causes of death. However, spinal cord injuries were statistically more frequent in mountain accidents. CONCLUSION: So, it seems important to continuously warn population about dangers of this playground.