An ultra marathon is any running event longer than a traditional marathon, which is 26.2 miles (42.195 kilometers). Typical ultramarathon distances start at 50 kilometers (about 31 miles) and can go up to 100 kilometers, 100 miles, or even longer, sometimes reaching distances of 200 miles or more. There are also timed ultra events where runners compete to cover the most distance within a set time, such as 6, 12, or 24 hours. In summary, an ultramarathon is any race longer than 26.2 miles, with common distances including 50K (31 miles), 50 miles, 100K (62 miles), and 100 miles, with even longer multiday races existing.