Porthemmet is a palm-fringed Cornish beach where topless sunbathing is encouraged and visitors are always made to feel welcome. But travellers following directions to this semi-tropical paradise will find themselves going nowhere.

Porthemmet was invented by a bored Cambridge graduate as a spoof. His website has received more than 6,000 hits and has a huge following on Facebook, but locals say it is a cruel joke that could harm the economy.

The name was the first giveaway as “emmet” is the Cornish word for ants and a derogative term used by locals to describe the tourist hordes who descend on the county each summer.

The website describes Porthemmet as Cornwall’s “largest beach” and claims it is the only beach in Britain to allow topless sunbathing and “looks more like a tropical paradise”.

The site suggests that visitors inform locals that they are an “emmet”, which it states is someone who loves Cornwall. It also instructs them not to listen to locals who claim not know where the beach is. The website claims: “There is a private joke in Cornwall whereby locals will pretend not to know where Porthemmet beach is. Don’t be fooled.”

Jonty Haywood, of Truro, Cornwall, said that he came up with the idea after hearing of a similar prank in a Scandinavian city. “Most people think it’s funny. Some discussions have got fairly heated regarding the general dislike of tourists versus their input into the Cornish economy.”

Julia Cox, from VisitCornwall, the Cornwall tourism board, said: “We really don’t want people thinking that Cornwall is hostile to tourists because that is not the case. Tourism is the most important part of the local economy in Cornwall.

“We can see that this website is meant as a joke, but we don’t want it to make people feel unwelcome.”

But Malcolm Bell, chief executive of South West Tourism, said that the hoax may not be bad for tourism. He said: “Any publicity is good publicity, It does mean we’re talking about Cornwall and it may bring people down to discover beaches that do exist.”

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