Summary Background Compliance with guidelines for the management of ST-segment elevation myocardial infarction (STEMI) may be difficult in hard-to-access areas. Aims To analyse the characteristics, management and outcome of STEMIs occurring at altitude in the French Alps and managed by mobile medical emergency units. Methods From January 2006 to December 2008, from the prospective RESURCOR registry, 114 patients with a STEMI of less than 12 hours’ duration, occurring in a ski resort or at high altitude and managed by the RESURCOR care system, were identified. Baseline characteristics, treatments and in-hospital outcomes were analysed. Results Ninety-three per cent of patients were men; the mean age was 57 years. STEMIs occurred during or less than 1 hour after physical activity in 76.3% of cases (mainly during or after alpine/cross-country skiing). Killip class greater or equal to 2 and cardiac arrest were observed in 35% and 7.9% of cases, respectively. Fifty-two (45.6%) patients underwent thrombolysis and 62 (54.4%) had percutaneous coronary intervention (PCI). Median delays were: first call to treatment, 82 min (17–230 min); symptoms to treatment, 165 min (52–770 min). All delays were significantly longer for PCI than for thrombolysis. First call to treatment delay was less than 120 min in 98.1% of patients who underwent thrombolysis and in 51.6% who had PCI ( P < 0.0001). In-hospital survival was 96.5%. Conclusion Altitude STEMIs happen mainly during sporting activities. Clinical presentation is often severe, but an emergency coronary care network allows rapid reperfusion. These findings emphasize the need for an efficient network for STEMI management in geographically difficult-to-access areas.