Europe is the second smallest continent, with an area of 10,400,000 km² (4,000,000 square miles). Its borders are much disputed, reflecting cultural and political factors instead of geographical ones. There is much here for the traveller to enjoy, with a bewildering array of diversity and culture, cosmopolitan cities and spectacular scenery.
Europe defies easy categorisation, with its compact size and complex history. The following are five (loosely defined) regions.
See also: European Union, 25 European states in various stages of economic and political union.
There are no border controls between countries that have signed the Schengen Agreement. Likewise, a visa granted for any Schengen Agreement signatory country is valid in all other countries that signed the treaty.
These countries are: Austria, Belgium, Denmark, France, Finland, Germany, Greece, Iceland, Italy, Luxembourg, the Netherlands, Norway, Portugal, Spain and Sweden. Note that not all EU members have signed the Schengen treaty and not all Schengen treaty countries are members of the European Union.
At some airports, airlines will still insist on seeing your id-card or passport. Travel to and from a Schengen Agreement country to any other country will result in the normal border checks.
The Inter Rail (for Europeans) and Eurail (for everybody else) passes offer good value if you plan on traveling extensively around Europe (or even a single region) and want more flexibility than cheap plane tickets can offer.
Note: Russia and the Caucasus are sometimes considered to be a part of Asia.