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Nik Wallenda studied the plunging walls of the Little Colorado River Gorge before stepping out on a quarter-mile tightrope cable. "Whoo! That's an amazing view."

With that observation, the well-known aerialist embarked Sunday afternoon on a walk without a safety net or harness, 1,500 feet above the Little Colorado River Gorge in northeastern Arizona.

The successful, 22-minute walk on the 2-inch thick cable was monitored by people around the world via television and computer screens during a broadcast of Wallenda's most ambitious stunt yet.

They watched as the winds tested the Florida daredevil, and listened as he called on God to calm the swaying cable and as he paid homage to his famed great-grandfather. The stunt was the leading trending topic on Twitter on Sunday afternoon.

"It was unbelievable," he told reporters later. "It was everything I wanted it to be. It was extremely emotional. I got to the other end and started crying."

Hundreds of people watched from the remote site on the Navajo Nation in northeastern Arizona that led them past roadside vendors selling traditional jewelry and about a dozen protesters who consider the area sacred.

During his walk on the 2-inch-thick steel cable above the dry river bed near the Grand Canyon, Wallenda paused and crouched twice as winds whipped around him and the rope swayed. Gusts had been expected to be around 30 mph. He said they sent dust flying into his eyes.

"It was strenuous the whole way across. It was a battle. The winds were strong, they were gusty," he told reporters. "But there was never a point where I thought, 'oh my gosh, I'm going to fall.'"

Wallenda stepped slowly and steady throughout, murmuring prayers to Jesus almost constantly along the way. He jogged and hopped the last few steps.

"Thank you Lord. Thank you for calming that cable, God," he said about 13 minutes into the walk.

The Discovery Channel broadcast the even live. He wore a microphone and two cameras, one that looked down on the river bed and one that faced straight ahead.

The 34-year-old Sarasota, Fla., resident is a seventh-generation high-wire artist and is part of the famous "Flying Wallendas" circus family — a clan that is no stranger to death-defying feats.

His great-grandfather, Karl Wallenda, fell during a performance in Puerto Rico and died at the age of 73. Several other family members, including a cousin and an uncle, have perished while performing wire walking stunts.

Nik Wallenda grew up performing with his family and has dreamed of crossing the Grand Canyon since he was a teenager. Sunday's stunt comes a year after he traversed Niagara Falls earning a seventh Guinness world record.

About 600 spectators watching on a large video screen on site cheered him on as he walked toward them. A Navajo Nation ranger, a paramedic and two members of a film crew were stationed on the canyon floor.

The ranger, Elmer Phillips, he got a little nervous when Wallenda stopped the first time. "Other than that, a pretty amazing feat," Phillips said.

Discovery's 2-hour broadcast showcased the Navajo landscape that includes Monument Valley, Four Corners, Canyon de Chelly and the tribal capital of Window Rock.

Wallenda already is eyeing his next stunt, which he hopes will take him between the Chrysler and Empire State buildings in New York. As a nod to his Internet audience, he said he also would ask his Facebook and Twitter followers what the next challenge should be

But he said he would give up tightrope walking altogether if his wife and children ever asked him.

"That's a serious talk that we'll have. But absolutely, it weighs on heavy on me," he said.