Mountain running is a sport that involves running on mountainous terrain, often including steep trails, rocky paths, and varying elevations. It combines the challenges of endurance running with the unique obstacles presented by nature, such as changes in weather and altitude. Races can vary in distance and difficulty, ranging from short sprints to ultra-marathons. Participants in mountain running often train to build strength and stamina, as the uneven surfaces and inclines require different skills compared to road running. Events are held worldwide, with popular locations including the European Alps and the Rocky Mountains, attracting both amateur and professional athletes.