Mushers are about a third of the way through this year's Iditarod Trail Sled Dog Race, bounding across ice on America's third-longest river.
The world-famous, 1,000-mile journey across Alaska kicked off Monday in Fairbanks. It usually starts 225 miles south in Willow, but poor conditions this year led organizers to reroute the trail around a mountain range.
Now, more than half of the race is being run on Alaska's river system - which at this time of year means ice.
The new terrain was of little concern to veteran contestants like Aliy Zirkle, who finished runner-up the past three years. She and others were mushing Wednesday on the Yukon River, headed toward a checkpoint in the village of Ruby.
''I'm not worried about too much river, too much overflow, cold or warm, or whatever,'' Zirkle said, calling it ''just another dog race.''
''We got a trail,'' she said. ''Let's put our heads down together and race it the best our teams can.''
The finish line remains in the Bering Sea coastal town of Nome.
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