An American stuntman has become the first person in more than a century to cross the Niagara Falls on a tightrope. Nik Wallenda, 33, was watched by an estimated one billion TV viewers and more than 125,000 sightseers at the famous gorge. He took 25 minutes to traverse the 1,800ft gap from Canada to the US on a 2 in-thick steel cable on Friday night.