Daredevil Nik Wallenda became the first person to walk across Niagara Falls on a high wire.
Tens of thousands of people gathered at the falls Friday night and millions more were believed to be watching on television as Wallenda crossed some 200 feet in the air on a two-inch-wide wire strung over the raging waters of Horseshoe Falls, the largest of the three falls that make up Niagara Falls.
Wallenda trotted in his final steps across the wire and stepped into Canada, barely 25 minutes after he started.
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After he greeted his wife and family, Wallenda was approached by customs agents, who asked him for his passport, which he presented.
"No, I'm not carrying anything over. I promise," he said.
"What is the purpose of your trip sir?" the agent asked.
"To inspire people around the world," Wallenda said.
Wallenda said the mist and the winds midway across the walk were the biggest challenge.
"It's all about the concentration, the focus, and it all goes back to the training," he said.
"I'm grinning from ear to ear because I can see I'm here. I made it," he added.
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Others have crossed the Niagara River itself, but never over the falls. Wallenda said that Friday night's feat was the fulfillment of a lifelong dream as well as a chance to honor his great-grandfather, legendary funambilist Karl Wallenda, who died after falling from a tightrope in Puerto Rico in 1978.
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Wallenda, 33, has called his great-grandfather his "biggest inspiration" and said he was thinking of him during the stunt. The 1,500-foot walk between Goat Island in the U.S. side to Table Rock in Canada was fraught with unforgiving natural conditions: blinding mist and drafts created by the force of the waterfalls crashing down on the Niagara River.
Those obstacles notwithstanding, Wallenda told reporters Thursday that he hopes the walk will be "peaceful and relaxing."
"Often, I'm very relaxed when I'm walking on a cable like that," he said, but he added that the historic nature of the event could also mean "there'll be some tears involved."
Preparing for the walk took months. In addition to actually practicing for the walk, Wallenda had to secure permission from both U.S. and Canadian authorities. On the Canadian side, giving Wallenda the go-ahead meant granting a one-time exemption on a 128-year ban on stunts. Wallenda's team also had to devise and implement measures to steady the wire and guarantee that, should Wallenda stumble, safety equipment would keep him from plunging down into the gorge.
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Friday's event is expected to bring a major boost to tourism in the Niagara Falls region, which sees 13 million visitors at the falls each year.
"Over a billion people by Monday will have known the story of Nik Wallenda over Niagara Falls," Tim Clark, of the Buffalo-Niagara Film Board, told ABC News affiliate WKBW, "and I think that's just fantastic reinforcement for our tourism industry here in western New York."
According to preliminary Nielsen ratings, when Wallenda finished his walk from 10:30 to 11 p.m., 13.1 million viewers were watching, and during the 9-11 p.m. two-hour broadcast, an average of 10.1 million people were tuned in.
As for Wallenda's next megastunt, he already has the permits to become the first man to ever walk a wire across the Grand Canyon.