I am not sure, maybe I can figure it out, however there are a few countries joining the European Union and will change from their currency to the Euro. The price will go up, anyone that wish to visit Eastern Europe should do so before this happens.
So I am on the Pre-Euro Tour, I enter Europe in Berlin and will proceed east...
The ten new Member States that joined the EU on 1 May 2004
I think these countries will change to the Euro, if you know when, please post in the comment below here, I just know the clock is burning and when they change to the Euro the prices will probably rise a minimum of 25 percent for travel.
I will bin Berlin, Germany - Already uses Euro next monday, the 13 of June.
The Pre-Euro Tour