Saying Nik Wallenda performed a difficult task yesterday is an understatement.

He is an acrobat in dark jeans and no shoes who carried a 42-pound balancing pole across a slippery, nickel-sized wire about 200 feet above the Allegheny River. He does not know how to dive into water and thus faced the possibility of immediate death (or, if he were lucky, paralysis). This is a man who had seven relatives who died during circus acts.

It was clear that at least some of the tens of thousands of spectators at the event were mindful of the danger.

"Watching a high wire act is like watching a race," said Jay Loomis of Cranberry. "Why do people go to car races? To see the crashes."

But Mr. Wallenda, 30, said before the event that he would not complete the act if he did not feel comfortable with the conditions.

The world record holder remained rather calm while walking the rickety, 1,100-foot steel wire, held up by a crane on the 10th Street Bypass, another in front of 12 Federal Street and support wires all attached to the Roberto Clemente Bridge. He paused every couple of minutes to bend down; he waved to the cheering crowds and let his arms rest from the pole. At only one point did he stop his walk, to steady his balancing pole against the strong winds.

It took him 25 minutes to walk from the 10th Street Bypass to the middle of Federal Street, the headline event for the Three Rivers Regatta this July 4 weekend. As he came down on the crane's hook, the crowds cheered and took pictures.

How did he feel?

"It was amazing," he said. "The view is amazing."

Of course, the event is not the grandest act he performed -- or will perform.

Mr. Wallenda has already set two Guinness world records. He set his first in a family act in Japan, where he and seven others formed a pyramid on a high wire. Last October, he set a record for longest and highest bicycle ride when he rode 135 feet over the streets of Newark, N.J. He aims to set another world record -- and family dream -- in the fall: a high wire walk over the Grand Canyon.

Yesterday's performance, while nowhere near that grandiose, impressed the Regatta crowd watching from both along the river and near the concession stands of the Clemente Bridge.

"Turn around and go back! [was] what I was thinking," said Jeff Toole, 45, of Castle Shannon, who sat by the river on the North Shore.

During the last week, Pittsburgh suffered through scattered thunderstorms and showers. Event organizers set a rain date for tomorrow in case the weather made the rope too slippery or too shaky.

But despite the rain, Mr. Wallenda came to the Clemente Bridge on Thursday morning to set up the wire and its support cables. The cranes came in around 6 p.m. Thursday to hoist the wires. Yesterday, Mr. Wallenda gave his final approval of the setup, which was prepared with the help of his father and head rigger, Terry Troffer, 54.

Mr. Troffer, who last performed a circus act earlier this decade, said he would have loved to perform the act when he was younger, but it was Mr. Wallenda's time to shine. All the father does now, he said, is make sure the rigging is safe.

Mr. Troffer said Mr. Wallenda practiced for the act a handful of times in their Sarasota, Fla., backyard about a month ago -- though only from 10 feet off the ground. The rope is rigged differently than in past Wallenda family acts, so Mr. Wallenda wanted to determine how the walk would be different before yesterday's show, Mr. Troffer said.

There were some mishaps yesterday, though. Mr. Wallenda's team ordered an ungreased galvanized steel wire, but they received an oily one. Throughout the walk, it rained.

After a victory lap on a boat around the Allegheny River, Mr. Wallenda said he had no doubts while up on the wire. He added that it is "great prep for the Grand Canyon."

Mr. Wallenda's act comes to Pittsburgh on behalf of ISM-USA, the creative management team that is running the regatta for the second year. The regatta will last until tomorrow.