The top four finishers in the last Iditarod , the renowned 1, 150-mile dog-sled race across Alaska, were all over 50 years old.

FORBES: World's Most Dangerous Races

More than 100 canine competitors are taking part in the annual Aviemore Sled Dog Race.

BBC: Aviemore dog sled race under way

The second day of the annual Aviemore Sled Dog Race has been cancelled because of safety concerns.

BBC: Aviemore dog sled race cancelled over safety concerns

Dallas Seavey also is among six past winners of the 1, 000-mile Yukon Quest International Sled Dog Race, held just weeks before the Iditarod.

NPR: Iditarod Kicks Off With Festive Ceremonial Start

Dan Seavey co-founded the Iditarod Trail Sled Dog Race in 1973.

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NOME, Alaska (AP) A 53-year-old former champion has won the Iditarod Trail Sled Dog Race to become the oldest winner of Alaska's grueling test of endurance.

NPR: 53-Year-Old Musher Becomes Oldest Iditarod Champ

ANCHORAGE, Alaska (AP) Mushers and their dogs took a leisurely jaunt through Anchorage on Saturday in the ceremonial start of Alaska's Iditarod Trail Sled Dog Race.

NPR: Iditarod Kicks Off With Festive Ceremonial Start

ANCHORAGE, Alaska (AP) Four-time champion Martin Buser held on to the lead Saturday in Alaska's Iditarod Trail Sled Dog Race, hoping to be only the second musher to ever claim a fifth title in the race's 40-year-history.

NPR: Iditarod Front-Runner Hopes To Claim 5th Win