Holiday resorts that are located in attractive tourist locations are a terrorist target and the threat is high.
Those include the horror blasts in Belgium, when Brussels was targeted by a number of explosions.
The north European country was already on high alert following the attacks in Paris some months before.
Germany is the latest nation on the continent to have its risk rating increased by the Foreign Office.
The country last year saw the cancellation of an international fixture with Holland after receiving information of a planned attack similar to the Islamic State assault on Paris in November.
Nations surrounding the Mediterranean sea also face major warnings, with Morroco the latest to get the most severe rating.
That decision was made in November after the African nation helped raid an ISIS terror cell.
Winter sun favourite Egypt is also among the danger zones, with many families chosing to dodge Sharm el-Sheikh after the Russian plane crash which killed all 224 people on board when it plumeted into the desert in Sinai. ISIS claimed responsibility for that attack.
The Mediterranean coast has a number of dangerous zones that are regularly visited by holidaymakers both across Europe and Africa.
The Foreign Office changed its risk levels for Tunisia, advising people not to travel to the south and western areas, following the killing of 37 on a tourist beach.
France, which saw horrific terror attack in Paris in November, was already at high risk level since the Charlie Hebdo attacks, six months ago.
Spain – which sees 12 million Brits visiting each year to sunny destinations such as Ibiza, Majorca, Barcelona and the Costa Del Sol – has also had its threat level heightened by the British Government.
Recent alerts for the region included fears Britons in the Costa del Sol could be targeted.
The terror threat was put to maximum after Spain’s security forces disrupted a number of groups who were recruiting people to travel to join terrorists in Syria and Iraq last June. Its government also believed they were plotting attacks across Europe.
The murders in Tunisia also took place at a resort which has two hotels, both operated by Spanish firm RIU.
Interior Minister Jorge Fernandez Diaz said the decision was made due to the “proximity of our country to the places where some of these attacks took place”.
He added: “I have adopted that decision. We are at war with barbarism against civilisation.”
Spain and France join African nations Algeria, Tunisia and Egypt on a high level, while Libya – embroiled in civil war – is sandwiched in between.
Turkey, which neighbours war-town Syria, is another British tourist destination on high alert.
It has recently seen a number of attacks in Istanbul and Ankara with a high number of fatalities.
Other holiday hotspots are currently on a general threat level.
These include Greece, which receives one million British visitors each year, as well as Italy and west Africa’s Morocco.
Other popular destinations for Brits seeking sun have an underlying threat, meaning attacks are unlikely, include Croatia, Bulgaria and Portugal, which has over two million British visitors each year.