The Schengen area is the largest free-travel area in the world, with currently 22 EU countries participating (Austria, Belgium, Denmark, Finland, France, Germany, Greece, Italy, Luxembourg, Netherlands, Portugal, Spain, Sweden, Czech Republic, Estonia, Hungary, Latvia, Lithuania, Malta, Poland, Slovakia and Slovenia), as well as 4 associated non-EU countries (Norway, Iceland, Switzerland and Liechtenstein). Ireland maintains an opt-out on the abolition of internal border controls.
Countries wishing to join the Schengen area must undergo a series of Schengen evaluations to confirm whether they fulfil the conditions necessary for the application of the Schengen rules.
