An Australian woman had to cut short her Cuba-to-Florida swim attempt yesterday after jellyfish put an end to her effort, reports Australia's ABC. Chloe McCardel, who would have been the first person to swim the 103-mile distance without a shark cage, called it quits after 11 hours and multiple jellyfish stings—which often end swimmers' attempts at the feat. McCardel will now consider whether to reattempt the swim she called "the hardest in the world today," the BBC reports. Her husband says they will revisit how to deal with jellyfish, but cost is a factor. "It's in the realms of $200,000 in order to be able to mount one of these challenges."