In the European Union you can operate your unmanned aircraft under the same rules in Austria, Belgium, Bulgaria, Croatia, Republic of Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Poland, Portugal, Romania, Slovakia, Slovenia, Spain and Sweden. These countries are also member of EASA, the European Aviation Safety Agency. The EU countries issue EASA pilot certificates, valid in all EU countries.
Switzerland, Norway and Iceland are not part of the European Union, but they are participating in EASA as official member states. EASA pilot certificates issued in EU countries are also valid in these three countries and vice versa. Sharing the same flight rules doesn't mean that flying in any country is always the same thing. Every country has its own no-fly zones. For instance, in France and Germany it concerns towns and villages. Night flights are prohibited in the Netherlands.