There’s an old Max Miller joke about a little boy saving his pocket money.

Asked what he was saving for he said: ‘So when I’ve got £5 I can spit on a bus’. Travellers abroad this summer might well think of saving their euros because, apart from the possibility of being stopped by bogus officers in Spain (near Marbella, apparently), the unwary holidaymaker can land in trouble worldwide.

In Spain and France it is apparently illegal to drive wearing flip-flops or have groceries on the back seat of a convertible. Most of the regulations are sensible but some may be urban myths. Certainly, the Foreign Office has recently pointed out that chewing gum or smoking in public in Singapore may lead to a fine.

Nothing is too small for the enterprising gangster. Years ago the soi-disant ‘Boss of Britain’s Underworld’ Billy Hill controlled the sale of bird feed in Trafalgar Square. I assume the Mafia had a similar lock on St Mark’s Square, but since 2008 feeding the pigeons in Venice has been an offence. The same applies in San Francisco. While in Florence do not eat on church steps or in church yards. There are also restrictions on eating near public buildings in Italy.

Dimmed headlights are daytime requirements in Nordic countries. In Denmark, a check under the car for sleeping children is required before starting the engine. Flushing a lavatory after 10pm in a residential block is not permitted in Switzerland.

Wearing high heels on archaeological sites such as the Acropolis in Greece is forbidden. Apparently stilletos cause more pressure than an elephant. It is illegal to wear bathing costumes off the beach in Barcelona or to swear in Virginia Beach in the States.

Further afield, it is illegal to bring Vic and other products containing codeine or pseudoephedrine into Japan, where it is also technically forbidden for men over 40 to have waist measurements exceeding 80cm. Presumably sumo wrestlers are exempt. Stepping on currency is an offence in Thailand, as is leaving your house without underwear.

Finally, it is seemingly illegal to urinate in the ocean off Portugal – although this might be a difficult offence to prove.

James Morton is a writer and former criminal defence solicitor