Almost 20% of children aged eight to 15 have never paddled in the sea, either in the UK or abroad, according to a survey.
And more than two in five in this age range have not been on a plane, the poll by travel agent www.sunshine.co.uk found.
The survey also revealed that two-thirds of eight to 15-year-olds have never been camping, 52% have not been on a boat and 71% have not stayed in a caravan.
Based on responses from 1,399 children aged eight to 15, the survey also showed that 52% had only been to one other country.
Also, 32% had never built a sandcastle on the beach and 37% had never seen a crab.
Asked for a favourite overseas holiday destination, 34% of the children opted for a Disney resort.
Sunshine.co.uk co-founder Chris Brown said: “I think it’s incredibly sad that so many children haven’t paddled in the sea. It’s something every young person should have experienced.
“I think with advancements in technology, such as games consoles and computers, more kids are staying indoors and not wanting to go out into the open air, which is an awful shame.”