It is no longer necessary to change money or convert various European currencies' exchange rates if you are travelling either within or to countries within the euro zone.
The euro, foreign currency and other forms of payment can be brought into and taken out of Germany without restrictions.
Travellers from the twelve member states of the European Monetary Union (Austria, Belgium, Germany, Finland, France, Greece, Ireland, Italy, Luxembourg, Netherlands, Portugal and Spain) can pay in euros by bank transfer or cheque.