An ultramarathon is any running event longer than the traditional Marathon length of 42.195 kilometers (26.21875 miles, 46,145 yards).
There are generally two types of ultramarathon runs: events that cover a specified distance, and events that take place during a specified time frame (with the winner covering the most distance in that time).
The format of these events and the courses vary, ranging from single or multiple loops (some as short as a 400-meter track), 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. Trail races are run on dirt roads or mountain paths, though some are run on little or no paved surfaces. Usually, there are aid stations every 5 to 15 km apart, where runners can replenish food and drink supplies or take a short break.
- 50 miles
- 50 km
- 100 kilometers
- 100 miles
- 24 hour events
- 48 hour events
- 72 hour runs
- 6 Day race
- 7 Day race
- 10 Day race
- 1000 miles
- 3100 miles
The format of these events and the courses covered are quite variable, ranging from single or multiple loops (some as short as a 400 meter track), to point-to-point road or trail races. Many ultrarunning events, especially trail challenges, are characterized by 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 five to fifteen km apart, where runners can replenish food and drink supplies or take a short break.
Timed events range from six, twelve or 24 hours, to two, three and six days (known as 'multi-day' events). Timed events are generally run on a track or a short road course, often one mile or less.
Ultramarathons over the world
Ultramarathons are run all over the world, and over 70,000 people complete an ultramarathon every year. A list of the most popular ultra marathons can be found under the subsection "Well-known ultramarathons" below.
Ultrarunning in Africa
Several ultradistance events are held in Africa. South Africa hosts the world's oldest and largest ultramarathon, the 84km Comrades Marathon. Approximately 12,000 runners complete Comrades each year, and approximately 20,000 in 2000. It also hosts the 56 kilometer long Two Oceans Marathon in Cape Town every spring which attracts 7,000 to 10,000 runners.
Ultrarunning in Asia
Ultrarunning in Australia and New Zealand
The first ultramarathon held in Australia and New Zealand was likely a track 100km in New Zealand. Today, Australia and New Zealand are host to approximately 100 ultramarathons each year. One of the most famous Australian ultra Marathons was the Westfield Ultra Marathon, an annual race between Sydney and Melbourne which was contested between 1983 and 1991. Greek runner Yiannis Kouros won the event five times during that period. Australia is also the home of one of the oldest 6 Day races in the world, the Cliff Young Australian 6 Day race, held in Colac, Victoria. The race is held on a 400 meter circuit at the Memorial Square in the centre of Colac, and has seen many epic battles since its inception in 1984. The 20th Cliff Young Australian 6-day race was held between the 20-26 Nov 2005. Kouros rewrote the record book in that event when he beat his existing world 6-day track mark and set a new mark of 1036.851 km.
Ultrarunning in Europe
Ultrarunning is also quite popular in Europe, where over 200 ultramarathons are held each year, among the biggest the 100k of Bienne]] and the 72.7k Rennsteiglauf in the Thuringian Forest. The second oldest ultramarathon in the world, London to Brighton, was widely considered to be among the most prestigious titles until its retirement in 2005. The earliest written documentation of ultrarunners came from Icelandic sagas. The history of ultrarunners and walkers from the Victorian Era has also been documented. The IAU hosts annual European Championships for the 50k, 100k and 24 hours. The European Ultramarathon Cup (ECU) is an annual series covering several of the biggest races in different European Countries. An extreme challenge in Germany is the annually multiday Deutschlandlauf (German Run) over 1200km
Ultrarunning in North America
There are several hundred ultramarathons held annually in North America. One of the most popular is the Western States , the world's oldest 100-mile trail run. The race began unofficially in 1974, when local horseman Gordy Ainsleigh's horse for the 100-mile Tevis Cup horse race came up lame. He decided to travel the course on foot, finishing in 23 hours and 47 minutes.
One of the first documented ultramarathons in North America was held in 1926, as part of the Central American Games. Tomas Zafiro and Leonicio San Miguel, both Tarahumara Indians, ran 100K from Puchuca to Mexico City in 9 hours and 37 minutes. At the time, the Mexican government petitioned to include the 100K in the 1928 Summer Olympics in Amsterdam, however nothing came of these efforts.
In April, 2006, the American Ultrarunning Hall of Fame was established by the American Ultrarunning Association (AUA). Candidates for the Hall of Fame are chosen from the 'modern era' of American ultras, beginning with the New York Road Runners Club 30 Mile race held in 1958. The Inaugural inductees were Ted Corbitt, a former US Olympian, winner of the aforementioned race in 3:04:13, and co-founder of the Road Runners Club of America, and Sandra Kiddy, who kicked off her ultra career at age 42 with a world record at 50 kilometers, 3:36:56, and who went on to set a string of US and world ultra records.
Road and dirt paths
- Comrades Marathon
- Grand Union Canal 145 mile Race
- London to Brighton (deceased)
- Two Oceans Marathon
Mountain and trails
- American River 50 Mile Endurance Run
- Angeles Crest 100 Mile Endurance Run
- Barkley Marathons
- Bear 100 Mile Endurance Run
- dirty girls 6, 12 & 24 hour Trail Race
- Grand Raid de la Réunion
- Hardrock 100 Endurance Run
- Leona Divide 50 Mile Run
- McNaughton Park Trail Runs
- Old Dominion 100 Mile Cross Country Run
- Quad Dipsea
- Rio Del Lago 100 Mile
- Swiss Alpine Marathon
- Tour du Mont Blanc
- The Vermont 100 Mile Endurance Run
- Wasatch Front 100 Mile Endurance Run
- The Western States Endurance Run
Ultra Challenge Series
- Lynchburg Ultra Series
- Montrail Cup
- RunFurther Ultrarunning Championships
- South Carolina Ultra Series
- Ontario Ultra Series (OUSER)
- Pacific Association Ultra Running Grand Prix
- Scottish Ultra Marathon Series SUMS
- SoCal Ultra Series
- The UltraRunner.net Race Series
Very long events and multidays
- Antibes 6 Day Race
- Athens International Ultra Festival
- Self-Transcendence 6 Day Race
- Self-Transcendence 10 Day Race
- Self-Transcendence 3100 Mile Race
- Deutschlandlauf 1200km German Run
- Yukon Arctic Ultra
Well-known ultramarathon runners of the past
- Alexis Lapointe, early Canadian ultra-distance running legend
- Birgit Lennartz, former Comrades Marathon winner
- Bjorg Austrheim-Smith, three time Western States winner
Famous ultramarathon runners
National and International Bodies
- International Association of Ultra Runners IAU
- AmericanUltra.org - American UltraRunning Association
- Australian Ultra Running Association (AURA)
- Association of Canadian Ultramarathoners
- Ultraruns Association of Moldova (ASM)
- CoolRunning.com - Westfield Sydney to Melbourne (links to pdf of book)
- ExtremeUltraRunning.com - Extreme Ultrarunning: Ultrarunning resources, Ultrarunning links and general ultra running information for the novice or veteran ultrarunner
- Multidays.com - Multiday and Ultrarunning News from around the world
-  = Alphabetical list of famous ultrarunners and results
- Planet Ultramarathon
- RealEndurance.com - UltraRunning All Time Result Lists
- Run100s.com - Stan Jensen's Web Site (comprehensive compilation of all things ultra)
- Sri Chinmoy Races.org - Hosts of Self-Transcendence 24/48 and multiday races around the world
- TrailRunner magazine
- UltraRunner.net - The UltraRunning link for the U.S.