The visa policy of the Schengen Area is a component within the wider area of freedom, security and justice policy of the European Union. It applies to the Schengen Area and to other EU member states except Ireland. The visa policy allows nationals of certain countries to enter the Schengen Area via air, land or sea without a visa for up to 90 days within any 180-day period. Nationals of certain other countries are required to have a visa to enter and, in some cases, transit through the Schengen area.
The Schengen Area consists of 25 EU member states and four non-EU countries that are members of EFTA: Iceland, Liechtenstein, Norway and Switzerland. Cyprus, while an EU member state, is not yet part of the Schengen Area but, nonetheless, has a visa policy that is partially based on the Schengen acquis.
Ireland has opted out of the Schengen Agreement and instead operates its own visa policy, as do certain overseas territories of Schengen member states.
Nationals of EU single market countries are not only visa-exempt but are legally entitled to enter and reside in each other's countries. However, their right to freedom of movement in each other's countries can be limited in a reserved number of situations, as prescribed by EU treaties.

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