Nik Wallenda, a member of the famed "Flying Wallendas" family of aerialists, has completed an historic tightrope crossing through the mist over Niagara Falls Gorge.
The 33-year-old made the walk from the U.S. side of the falls to the Canadian side, a journey of 1,800 feet (550 metres) over treacherous waters and rocks, in a little more than 25 minutes.
He then stepped from a two-inch wire (5 cm) onto safe ground in Canada to wild cheers from a crowd of thousands.
More than a century ago, an aerialist known as the Great Blondin walked a high wire strung farther down the gorge, but a trek over the brink of the falls had never before been attempted.
Along the way, suspended over the falls, Wallenda, took small, steady steps on a slick cable through swirling winds.
ABC, the television network that broadcast the event with a five-second delay, occasionally interviewed him along the walk, asking him about conditions and how he was coping.
"That mist was thick and it was hard to see at times," he said later in the walk, when he was asked about the greatest challenge. "Wind going one way, mist another. It was very uncomfortable for a while."
The network had also insisted he wear a safety tether - a first for the performer - that would connect him to the cable should he fall, and said it would stop broadcasting if he unhooked it.
Wallenda fought the condition at first, eventually agreeing. But he gave himself an out: he would unhook only if directed to do so by his father, who designed the harness and acted as his safety coordinator.
As it turned out, the tether was never tested. Wallenda walked the wire with what appeared to be perfect balance and confidence.
There were 4,000 tickets that sold out in less than five minutes when they went on sale in recent weeks, and crowds began gathering early on Friday.
"Hopefully it will be very peaceful and relaxing," Wallenda said beforehand. "I'm often very relaxed when I'm on the wire." He added, "There may be some tears because this is a dream of mine."
Since the Great Blondin took his high-wire walk, a ban had been in place on similar stunts over the famed falls. Wallenda waged a two-year crusade to convince U.S. and Canadian officials to let him try the feat. A private helicopter rescue team was part of the $1.3 million that Wallenda said he had spent on the walk.
Kathy Swoffer, of Port Huron, Michigan, who had set up a lawn chair hours before the event, said she had seen the Wallendas perform years earlier in Detroit.
"I think it's a person wanting to do what they do for a living and fulfilling a lifelong dream," she said.
Wallenda's great-grandfather Karl Wallenda died in 1978 during a walk between two buildings in Puerto Rico at age 73. Wallenda repeated that walk last year with his mother.
Wallenda said he had obtained permits for a future walk over the Grand Canyon in Arizona, which would be the first ever attempted and roughly three times longer than the walk over Niagara Falls.