The Teenage Cancer Trust has urged young people to learn how to protect themselves from over-exposure to the sun, reducing skin cancer risk.
The call comes after a survey by the charity found that 40% of young people lie in the sun for as much as two hours without any protection, believing it to be a safe length of time.
The survey of 13 to 24-year-olds found that 15% believe building a base tan using sunbeds prevents burning on holiday.
A tenth of teenagers hold the opinion that sunbeds are safe if they are used once a week, while a similar proportion think that fake tans can lead to skin cancer.
The survey also found that over a third do not wear sun cream in the UK even on hot days.
Over half do not have much knowledge of how to apply sun cream correctly, believing it should be rubbed in completely, whereas for full protection it should be patted gently on to skin with a visible film left on the surface.
Simon Davies, Chief Executive of the Teenage Cancer Trust, said: "Melanoma is fast becoming one of the most common cancers in young people so they need to learn how to protect themselves now."