Wallenda, 33, a seventh-generation member of the famed "Flying Wallendas" family of circus performers, is set to walk a 2-inch (5 cm) cable strung 1,800 feet (550 meters) across Niagara Falls gorge - the first such tight rope feat between the United States and Canada in more than a century.

This has been his dream since he was 6 years old, Wallenda said during a news conference held near the falls in upstate New York.

"I can guarantee nothing like this has ever happened anywhere in the world," Wallenda said of his planned walk 150 feet (46 meters) above the falls that span two countries.

"I've done walks that are higher and longer but none of them compare to this," he said.

Wallenda, of Sarasota, Florida, said he will train publicly for 10 days prior to the walk, from May 12 to 22, in a parking lot used by the Seneca Niagara Casino, located less than a mile (1.6 km) from the gorge.

Using a cable strung between two cranes at the site, Wallenda is set to practice using equipment to simulate the high-wind conditions and moisture he expects to encounter.

As for which country Wallenda will be in when he steps out onto the wire, he said weather will dictate that and a decision will be made closer to June 15. He said it's likely the walk, which is expected to take 30 to 40 minutes, will take place in the early evening, when colored lights are used to illuminate the huge waterfalls.

A long-standing ban on such stunts in and around Niagara Falls has meant that no one has attempted a high-wire walk there in more than 100 years.

Gaining permission for the June 15 walk required almost two years of lobbying by Wallenda and politicians in upstate New York who hope the spectacle will translate into tourism dollars.

"We had to change two laws in two countries," Wallenda said. "I didn't know how far I would get. There's a history of people who have been denied."

Wallenda's initial support came last September when New York Governor Andrew Cuomo signed a bill giving him one year to perform the feat. Canada initially opposed the stunt but then reversed itself in February and agreed to allow it with a provision barring a similar feat for another 20 years.

Wallenda holds several Guinness World Records including one for the highest tightrope crossing by bicycle and another for the longest.

(Editing by Barbara Goldberg; Editing by Will Dunham)

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