Europe

Hitchhiking in Europe is fun. There are many small countries to enjoy hitching through, motorways in the Western parts can be exceptionally good, and overall hitchhiking is relatively safe. Some countries such as Germany are quite easy to hitch around, for example, for the large distances in a single lift, or with the possibility to go really fast (especially where driving speed is not limited). England is usually good because of the relatively short waiting time. Most other countries are at the average or rather easy hitchability level, e.g. the Netherlands, Belgium and East European countries. Some other countries are considered bad for the long waiting times (like Spain and Italy) but even there you might get a ride if you are patient enough. Some people chose to skip a country, though, after standing in one place for over two hours - it is reasonable enough to do so if visually good hitch-hiking spot appears not working in some places.

Note: In France, Germany, Austria, Slovenia, Poland, Czech Republic, Hungary, Switzerland and Italy trucks are not allowed to use motorways on Sundays and on public holidays.  (Any other countries?) However, these restrictions do not apply to those granted an exception, such as trucks transporting perishable goods and fuel supplies.

Hitching is rather safe in Europe. However, a single female hitch-hiker takes a higher risk for obvious reasons.

For crossing the borders have a look at the Schengen Agreement. With a Schengen visa you can travel within a bunch of European countries.

When hitching longer distances it's generally good to stick to gas stations on the motorway. People there go long distances and it's not uncommon to find rides of 500 km and longer.

Maps
It is more convenient to take a map on your trip but if you don't do so it is no big deal - some people actually prefer to get a feeling of lost nomads and to trust their own senses. For Western Europe the Marco Polo Euro Atlas is a great hitch-hikers's choice: it contains a detailed information about gas stations situated on motorways, and excludes less useful for hitch-hiking trips stuff like the index pages or city maps. For online usage:
 * hitchwiki.org/maps/ - based on OpenStreetMap and GoogleMaps
 * viamichelin.com
 * Map24.com - very good Java-Maps and routing
 * OpenStreetMap.org - free alternative

Main European Motorways
See European roads

Tips for each country
The United Nations Statistics Division defines Europe as following:

Northern Europe

 * Flag of Denmark.svg Denmark
 * Flag of Estonia.svg Estonia
 * Flag of Finland.svg Finland
 * Flag of Iceland.svg Iceland
 * Flag of Ireland.svg Ireland
 * Flag of Latvia.svg Latvia
 * Flag of Lithuania.svg Lithuania
 * Flag of Norway.svg Norway
 * Flag of Sweden.svg Sweden
 * Flag of the United Kingdom.svg United Kingdom of Great Britain and Northern Ireland

Autonomic Islands or Regions

 * Flag of Åland.svg Åland Islands
 * Channel Islands
 * Flag of Guernsey.svg Guernsey
 * Flag of Alderney.svg Alderney
 * Flag of Herm.svg Herm
 * Flag of Sark.svg Sark
 * Flag of Jersey.svg Jersey
 * Flag of the Faroe Islands.svg Faeroe Islands
 * Flag of the Isle of Man.svg Isle of Man
 * Flag of Norway.svg Svalbard and Jan Mayen Islands

Western Europe

 * Flag of Austria.svg Austria
 * Flag of Belgium (civil).svg Belgium
 * Flag of France.svg France
 * Flag of Germany.svg Germany
 * Flag of Liechtenstein.svg Liechtenstein
 * Flag of Luxembourg.svg Luxembourg
 * Flag of Monaco.svg Monaco
 * Flag of the Netherlands.svg Netherlands
 * Flag of Switzerland.svg Switzerland

Eastern Europe

 * Flag of Belarus.svg Belarus
 * Flag of Bulgaria.svg Bulgaria
 * Flag of the Czech Republic.svg Czech Republic
 * Flag of Hungary.svg Hungary
 * Flag of Moldova.svg Republic of Moldova
 * Flag of Poland.svg Poland
 * Flag of Romania.svg Romania
 * Flag of Russia.svg Russian Federation
 * Flag of Slovakia.svg Slovakia
 * Flag of Ukraine.svg Ukraine

Southern Europe

 * Flag of Albania.svg Albania
 * Flag of Andorra.svg Andorra
 * Flag of Bosnia and Herzegovina.svg Bosnia and Herzegovina
 * Flag of Croatia.svg Croatia
 * Flag of Greece.svg Greece
 * Flag of Italy.svg Italy
 * Flag of Kosovo.svg Kosovo
 * Flag of Macedonia.svg Macedonia
 * Flag of Malta.svg Malta
 * Flag of Montenegro.svg Montenegro
 * Flag of Portugal.svg Portugal
 * Flag of San Marino.svg San Marino
 * Flag of Serbia.svg Serbia
 * Flag of Slovenia.svg Slovenia
 * Flag of Spain.svg Spain
 * Flag of Turkey.svg Turkey
 * Flag of Cyprus.svg Cyprus

Autonomic Regions

 * Flag of Gibraltar.svg Gibraltar
 * Flag of the Vatican City.svg Holy See