“Avoid areas where protests are occurring due to the potential for disruption and violence,” urges the official travel advice for Australian visitors to the UK.

“Monitor the media for information and updates. Follow the instructions of local authorities.”

Every nation that is a significant “source market” for tourists issues guidance to its citizens about the threats they face. The authorities in Canberra do not urge Australians to leave the UK immediately (as they do for Lebanon), but they warn of terrorism “motivated by Islamic extremism, extreme right-wing ideology [or] the status of Northern Ireland.

But some of the warnings and assertions by foreign powers may mystify those who live in the UK.

These are some of the more unusual aspects of life in Britain that travellers are warned about.

Australia

“Health risks are broadly similar to those in Australia,” the Canberra government says. Really? Like the devastating bushfires, dust storms, tropical cyclones, crocodiles, sharks and “venomous insects, spiders and snakes in many parts of the country” that the UK Foreign Office warns British travellers to Australia about?

“If you’re not insured, you may have to pay thousands of dollars upfront for medical care.” Not true; Australians have a reciprocal health care agreement with the UK.

Petty crime in the UK “happens more often in summer”, according to the advice. The Australian government adds: “Regular strikes can occur across several industries, including ambulance services, hospitals and public transport.”

Canada

“Exercise a high degree of caution,” the United Kingdom travel advice for Canadians begins. The reason: the threat of terrorism.

Three areas of central London are picked out as high-crime areas: Piccadilly Circus, Trafalgar Square and Leicester Square. “Avoid showing signs of affluence,” Canadians are advised.

For those who choose to drive, roads “are often narrow and congested”, while “parking in London and other major city centres is limited and expensive”.

Ireland

“Irish citizens don’t require vaccinations for travel to Great Britain.” That’s a relief.

New Zealand

The Wellington government’s SafeTravel advice begins by pointing out: “The UK has a long history of terrorist attacks which have caused multiple deaths and injuries.

“Terrorist groups, individuals returning to the United Kingdom and Europe from areas of conflict, and individuals adhering to various forms of violent extremist ideologies, continue to make threats to conduct attacks in the United Kingdom.

“There is also an enduring threat of Northern Ireland-related terrorism.”

In terms of crime: “Petty crime such as bag and mobile phone snatching, pickpocketing and mugging is common, especially in urban centers, tourist locations and on public transport.”

United States

The US Embassy in London gives plenty of friendly travel advice to visiting Americans, for example on visiting Parliament on an organised tour or watching a debate in the House of Commons (for which US citizens require a Card of Introduction, obtainable from the embassy).

The State Department travel advice for the UK is less frivolous. Americans are warned: “The United Kingdom has very strict gun control laws, and importing firearms is extremely complicated.”

Many British people will be glad about that. But mobility is criticised: “Getting around in cities may be difficult at times because sidewalks can be narrow and uneven. Most London Underground and UK National Rail System stations are not readily accessible for people with disabilities.”

Finally, Americans are warned: “Beware of ‘impostors posing as undercover police officers and ‘fining’ tourists’ for bogus minor offences.”