It is becoming more and more fashionable to take trips in which you can visit several cities and, if possible, several cities. That is why Europe is one of the main vacation destinations for tourists from around the world, not only to visit the great capitals but also to see any other less famous but equally spectacular city.
Whether on a luxurious trip or backpacking, there is the possibility of visiting several European countries in a single trip and in a short time, enjoying at least its most important cities. As in any other place you are going to visit, in European destinations you also have to take into account the documentation you need to be able to move around without having any legal problem that may hinder your vacation.
Citizens of the European Union
People with the nationality of any of the member countries of the European Union have hardly any problems to be able to move around any country, and in many cases they do not need more than their DNI . What you should keep in mind in this case is that not all European countries belong to the European Union, so to visit them you do need a passport, both to enter and leave. Those countries are the United Kingdom, Ireland, Romania, Cyprus and Bulgaria.
Citizens who are not from the European Union
For people who are not from a country belonging to the European Union (including the Europeans mentioned in the previous point), it is mandatory to travel with a valid passport , and in some cases also with a visa. The visa can be obtained at the consulate or embassy that that country has in the country where you live, although the normal thing is that if you are not going to be more than three months you do not need it. If you need a visa, you can use it to enter any European country, whether or not it is a member of the EU.