How to get in Europe
Rules for entering Europe depend on where you are going. EU/EFTA citizens can travel freely throughout the continent (except Russia, Belarus and the Caucasus), so the following applies only to non-EU/EFTA citizens.
If you are entering a Schengen country and you plan to visit only other Schengen countries, you need only one Schengen visa. Only the nationals of the following non-EU/EFTA countries do not need a visa for entry into the Schengen Area: Albania*, Andorra, Antigua and Barbuda, Argentina, Australia, Bahamas, Barbados, Bosnia and Herzegovina*, Brazil, Brunei, Canada, Chile, Costa Rica, Croatia, El Salvador, Guatemala, Honduras, Israel, Japan, Macedonia*, Malaysia, Mauritius, Mexico, Monaco, Montenegro*, New Zealand, Nicaragua, Panama, Paraguay, Saint Kitts and Nevis, San Marino, Serbia*/**, Seychelles, Singapore, South Korea, Taiwan*** (Republic of China), United States, Uruguay, Vatican City, Venezuela, additionally persons holding British National (Overseas), Hong Kong SAR or Macau SAR passports.
These non-EU/EFTA visa-free visitors may not stay more than 90 days in a 180 day period in the Schengen Area as a whole and, in general, may not work during their stay (although some Schengen countries do allow certain nationalities to work - see below). The counter begins once you enter any country in the Schengen Area and is not reset by leaving a specific Schengen country for another Schengen country, or vice-versa. However, New Zealand citizens may be able to stay for more than 90 days if they only visit particular Schengen countries - see for the New Zealand Government's explanation.
If you are a non-EU/EFTA national (even if you are visa-exempt, unless you are Andorran, Monégasque or San Marinese), make sure that your passport is stamped both when you enter and leave the Schengen Area. Without an entry stamp, you may be treated as an overstayer when you try to leave the Schengen Area; without an exit stamp, you may be denied entry the next time you seek to enter the Schengen Area as you may be deemed to have overstayed on your previous visit. If you are unable to obtain a passport stamp, make sure that you retain documents such as boarding passes, transport tickets and ATM slips which may help to convince border inspection staff that you have stayed in the Schengen Area legally.
while British subjects with the right of abode in the United Kingdom and British Overseas Territories citizens connected to Gibraltar are considered "United Kingdom nationals for European Union purposes" and therefore eligible for unlimited access to the Schengen Area,
British Overseas Territories citizens without the right of abode in the United Kingdom and British subjects without the right of abode in the United Kingdom as well as British Overseas citizens and British protected persons in general do require visas.
However, all British Overseas Territories citizens except those solely connected to the Cyprus Sovereign Base Areas are eligible for British citizenship and thereafter unlimited access to the Schengen Area.
Further note that
(*) nationals of Albania, Bosnia and Herzegovina, Macedonia, Montenegro and Serbia need a biometric passport to enjoy visa-free travel,
(**) Serbian nationals with passports issued by the Serbian Coordination Directorate (residents of Kosovo with Serbian passports) do need a visa and
(***) Taiwan nationals need their ID number to be stipulated in their passport to enjoy visa-free travel.
The 90 days visa-free stay applies for the whole Schengen area, i.e. it is not 90 days per country as some assume. Citizens of the above countries who wish to travel around Europe for longer than 90 days must apply for a residency permit. This can be done in any Schengen country, but Germany or Italy are recommended, because many other countries require applicants to apply from their home countries.
Non-Schengen countries, on the other hand, maintain their own immigration policies. Consult the country article in question for details. If you wish to visit a non-Schengen country and return to the Schengen area, you will need a multiple-entry visa. Bulgaria, Romania, Ireland, and the United Kingdom are EU members, but they are not part of the Schengen Area. To add confusion Switzerland, Iceland and Norway are not EU members but part of the Schengen area, while Liechtenstein is neither a member of the EU or Schengen.
The implications of this are simple: countries in the EU maintain similar customs controls. Therefore, you do not need to pass through customs when travelling to a non-Schengen EU country, but you may need to pass through immigration controls. The converse is true for non-EU Schengen countries: you must pass through customs, but not immigration.
The following countries are members of the Schengen Area: Austria, Belgium, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, and Switzerland.
The Most Frequently Asked Travel Questions about Europe