ELIGIBILITY N.T.R. ________________________________________ For ultramarathon race Natura Trail Race (NTR) men and women can participate born until the year 1997. We need prerequisites for participation in this race. More specifically finishing a trail race of 40km and above in 2017 is required. But participants must be aware of the management difficulties of doing so and have experience in mountain races. On completion of the registration form participants should report the type of the event that the athlete exercises as well as a brief biography of the most important mountain races that took place and finished in the years 2015-2017. The maximum participation endorsement 200 athletes.