A tightrope daredevil has completed a walk that took him quarter of a mile over the Little Colorado River Gorge in north-eastern Arizona.

Daredevil Nik Wallenda is set to walk a 1,800 foot (549m) tightrope across Niagara Falls this summer, a feat the seventh-generation member of the famed Flying Wallendas said has been his childhood dream.

A seventh-generation high-wire daredevil has pedalled a bicycle across a precarious line strung between two hotel towers in an attempt to break his own world record.