The Iditarod Trail Sled Dog Race, more commonly known as The Iditarod, is an annual long-distance sled dog race run in early March. It travels from Anchorage to Nome, entirely within the US state of Alaska. Mushers and a team of between 12 and 14 dogs, of which at least 5 must be on the towline at the finish line, cover the distance in 815 days or more. The Iditarod began in 1973 as an event to test the best sled dog mushers and teams but evolved into today's highly competitive race.

Teams often race through blizzards causing whiteout conditions, sub-zero temperatures and gale-force winds which can cause the wind chill to reach 100 F (73 C). A ceremonial start occurs in the city of Anchorage and is followed by the official restart in Willow, a city 80 miles (129 km) north of Anchorage. The restart was originally in Wasilla through to 2007, but due to too little snow, the restart has been at Willow since 2008. The trail runs from Willow up the Rainy Pass of the Alaska Range into the sparsely populated interior, and then along the shore of the Bering Sea, finally reaching Nome in western Alaska. The trail is through a rugged landscape of tundra and spruce forests, over hills and mountain passes, across rivers and even over sea ice. While the start in Anchorage is in the middle of a large urban center, most of the route passes through widely separated towns and villages, and small Athabaskan and Iupiat settlements. The Iditarod is regarded as a symbolic link to the early history of the state and is connected to many traditions commemorating the legacy of dog mushing.

The race is an important and popular sporting event in Alaska, and the top mushers and their teams of dogs are local celebrities; this popularity is credited with the resurgence of recreational mushing in the state since the 1970s. While the yearly field of more than fifty mushers and about a thousand dogs is still largely Alaskan, competitors from fourteen countries have completed the event including Martin Buser from Switzerland, who became the first foreign winner in 1992. Fans follow the race online from all over the world, and many overseas volunteers also come to Alaska to help man checkpoints and carry out other volunteer chores.

The Iditarod received more attention outside of the state after the 1985 victory of Libby Riddles, a long-shot who became the first woman to win the race. The next year, Susan Butcher became the second woman to win the race and went on to win in three more years. Print and television journalists and crowds of spectators attend the ceremonial start at the intersection of Fourth Avenue and D Street in Anchorage and in smaller numbers at the checkpoints along the trail.

Mitch Seavey set the record fastest time for the Iditarod in 2017, crossing the line in Nome in 8 days, 3 hours, 40 minutes and 13 seconds, while also becoming the oldest winner.

Libby Riddles (born April 1, 1956) is an American dog musher, and the first woman to win the Iditarod Trail Sled Dog Race.Riddles was born in Madison, Wisconsin, to Willard and Mary Riddles, and moved to Alaska (from Minnesota; she had been living in St. Joseph while attending Apollo High School in St. Cloud) just before her 17th birthday. She saw a sprint race and fell in love with mushing. Her first race was the Clines Mini Mart Sprint race in 1978, in which she won first place. After finishing 18th and 20th in the 1980 and 1981 Iditarod races, she decided to breed her own sled dogs in order to advance. She moved to Shaktoolik, Alaska and worked as a fish seller for a short period while training her dogs, then moved to Teller, Alaska where she met Joe Garnie; they became partners and started breeding and training dogs together.

On March 20, 1985, Riddles won the Iditarod Trail Sled Dog Race, becoming the first woman to do so. She wrote three books about her adventures and also became a professional speaker. In 2007, her Iditarod Trail Race victory was inducted as a "Hall of Fame Moment" into the Alaska Sports Hall of Fame.After winning the Iditarod, she decided to live like an Alaska Native for six years.