The Schengen Area (pronunciation: /ˈʃɛ/, /ˈʃɛŋ/) is an area comprising 26 European states that have officially abolished passport and all other types of border control at their mutual borders. The area mostly functions as a single country for international travel purposes, with a common visa policy. The area is named after the Schengen Agreement. States in the Schengen Area have strengthened border controls with non-Schengen countries.
Twenty-two of the twenty-eight European Union (EU) member states participate in the Schengen Area. Of the six EU members that are not part of the Schengen Area, four – Bulgaria, Croatia, Cyprus, and Romania – are legally obliged to join the area, while the other two – the Republic of Ireland and the United Kingdom – maintain opt-outs.