A travel alert was issued by the US State Department on Thursday telling Americans to avoid travelling to the continent in the next few months because of the “continued threat”.
It warns ISIS and affiliated groups are continuing to target tourist spots, transport hubs and shopping malls.
The US State Department said: “Recent, widely reported incidents in France, Russia, Sweden, the United Kingdom, Spain, and Finland demonstrate that the Islamic State of Iraq and ash-Sham (ISIS or Da’esh), al-Qa’ida, and their affiliates have the ability to plan and execute terrorist attacks in Europe.
“While local governments continue counterterrorism operations, the Department remains concerned about the potential for future terrorist attacks.
“US citizens should always be alert to the possibility that terrorist sympathisers or self-radicalised extremists may conduct attacks with little or no warning.”
And it says hotels, clubs, restaurants and parks could also be part of the terror group’s hitlist.
It warned: ”US citizens must remain alert to the possibility that extremists and sympathisers may carry out attacks without prior notice.
“Terrorists persist in employing a variety of tactics, including firearms, explosives, using vehicles as ramming devices, and sharp-edged weapons that are difficult to detect prior to an attack.”
The alert, which does not expire until November 30, urges people to review whether there are security alerts in the destination countries before making a trip.
It comes after a string of atrocities in countries across the continent, with recent attacks in Barcelona, London and Manchester.
Any fall-off in tourism from the US would badly effect European countries, particularly Spain which suffered an attack at the height of the tourist season.
Sixteen people were left dead when a group of jihadists carried out attacks in Barcelona and nearby Cambrils on August 17 and 18.