“Rebel trails” is a unique marathon carried out at a historical place, part of Blue Rocks Nature Park, located in the eastern and most accessible part of the biggest Bulgarian mountain – Stara planina (Balkan Mountains). The trace passes a specific rocky massif with an alpine type relief defensed by 14 antique and medieval fortresses. Due to its key location this is the site where main road arteries have been passing the mountain since ancient times. On the other way, specificity of its relief: exposed rocky peaks and ridges, steep slopes and rocks, presence of lots of caves and waterfalls, makes the massif hardly accessible and preferred shelter for many rebels (haidouks) in the past. The marathon “Rebel trails” is unique having a trace entirely consisting of age-old paths once used by haidouks, which nowadays exist as touristic routes. The trace passes through or nearby all known but not well studied fortresses, having as a goal to popularize them. The marathon is organized in the last week of October, when winter is on the doorstep. This gives a unique opportunity for carrying it out in different weather conditions and with different difficulty level each year.