NUTS Karhunkierros Trail Ultra

The route wanders along the magnificent Karhunkierros Trail in Oulanka National Park. The route is extremely demanding, consisting of steep uphill and downhill sections and uneven terrain, even snow!
Find out more: nutskarhunkierros.fi
What is ultra trail running or ultramarathon?
"An ultramarathon (also called ultra distance) is any sporting event involving running and walking longer than the traditional marathon length of 42.195 kilometres ( or 26.21875 miles).
There are two types of ultramarathon events: those that cover a specified distance, and events that take place during specified time (with the winner covering the most distance in that time). The most common distances are 50 kilometres (31.069 mi), 100 kilometres (62.137 mi), 50 miles (80.4672 km) and 100 miles (160.9344 km), although many races have other distances. The 100 kilometers is an official IAAF world record event.
Other distances/times include double marathons, 24-hour races, and multiday races of 1000 miles or even longer. The format of these events and the courses vary, ranging from single or multiple loops (some as short as a 400-meter track),[2] to point-to-point road or trail races, to cross-country rogaines. Many ultramarathons, especially trail challenges, have severe course obstacles, such as inclement weather, elevation change, or rugged terrain. Many of these races are run on dirt roads or mountain paths, though some are run on paved roads as well. Usually, there are aid stations every 20 to 35 km apart, where runners can replenish food and drink supplies or take a short break.
Timed events range from 6, 12, and 24 hours to 3 and 6 days and 10 days (known as multi-day events). Timed events are generally run on a track or a short road course, often one mile or less.
The International Association of Ultrarunners (IAU) organises the World Championships for various ultramarathon distances, including 50 km, 100 km, 24 hours and ultra trail running."
(Source:Wikipedia)