Travelling without being properly covered has been described as "extremely foolish" by a leading expert.
Sean Tipton, the press officer at the Association of British Travel Agents (ABTA), has said that it is also very irresponsible for those who are heading on adventure holidays to not consider taking out insurance.
Discussing the issue, he explained the potential problems that may arise without adequate cover.
"The worst case scenario is that if you broke your leg skiing in America and you didn't have insurance then you would be talking about a bill for tens of thousands of dollars," he explained.
"If it was a very bad break then they might decide that you should be flown back to the UK in an air ambulance and then you're getting into a hundred thousand potentially."
Recent research by the Foreign and Commonwealth Office found that 17 per cent of 18 to 35-year-olds have gone jet-skiing on the spur of the moment on holiday, while 14 per cent have also gone rock climbing at the last minute.
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