Travel within the European Union has become much easier in the last few years. Many EU member states have abolished all border controls (immigration and customs), meaning you can simply cross from one country to the next without stopping to show your passport or have your baggage checked. Effectively, the border has disappeared between member states that have ratified the relevant parts of the Schengen Agreement. So, you can travel freely between the following member states without passport or customs checks:
Austria, Belgium, Czech Republic, Denmark, Estonia, France, Finland, Germany, Greece, Hungary, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden and the two associated countries Norway and Iceland.
Note that you will still be subject to passport and customs checks when travelling from or to the UK or Ireland, since these countries have not signed the relevant parts of the Schengen Agreement.
Many EU member states use the euro as their currency. This means that you don’t have to change money when you travel between these member states, so you avoid paying commission and losing money because of differing exchange rates. The EU Economic and Financial Affairs page has information on the euro and which member states use it at the moment.
There are a lot of resources designed for young people who want to travel or volunteer in the EU. A good place to start is the European Youth Portal, which provides links to many travel-related organisations. The definition of “youth” varies, but it often means under 26 years old. Another useful website is Interrail – a scheme that allows European residents to travel cheaply in Europe by rail.