An Australian woman's family cycling holiday in the United States has ended in tragedy when she looked the wrong way while attempting to cross a busy Florida highway.

Elsise Hoath, 60, made a mistake many Australians do while in America, but her error was fatal.

Instead of looking left before crossing the road, she looked right as she would in Australia, and believing the highway was clear, stepped in front of a fast-moving Nissan Pathfinder 4WD without seeing it.