You pass from one country to another within the Schengen Area without any checks being carried out. The Schengen Visa makes it possible to visit all the countries in the Schengen Area and to cross internal borders without any further formalities.

Take care, though – the European Union and the Schengen Area are two separate areas! This list shows you the difference, and lets you check that the countries you are planning to stay in are all within the Schengen Area.