The visa policy of the Schengen Area is an element 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 stays of up to 90 days within a 180-day period. Nationals of certain other countries are required to have a visa either upon arrival or in transit. The Schengen Area consists of 23 EU member states and four non-EU countries that are members of EFTA: Iceland, Liechtenstein, Norway and Switzerland. Bulgaria, Cyprus and Romania, while EU members, are not yet part of the Schengen Area but, nonetheless, have 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. Their right to freedom of movement in each other's countries can, however, be limited in a reserved number of situations, as prescribed by EU treaties. Visa exemptions Freedom of movement citizens Citizens of EFTA member states Nationals of 'Annex II' countries and territories (visa waiver countries) Since 2001, the European Union has issued a list of countries whose nationals need visas (Annex I) and a list of those who do not (Annex II). The two lists are also adopted by Bulgaria, Cyprus and Romania, even though the three countries are not yet part of the Schengen Area. Nationals of the following countries and territories holding ordinary passports may enter the Schengen Area, Bulgaria, Cyprus and Romania without a visa, for short stays (usually 90 days within a 180-day period): Residents and holders of visas of Schengen states Holders of a long-stay visa or residence permit issued by a Schengen state or Monaco may also travel to other Schengen states, without an additional visa, for a stay of up to 90 days in any 180-day period. Short-stay visas issued by a Schengen state are also valid for all other Schengen states unless marked otherwise. Holders of a visa (even if limited to a specific country) or residence permit issued by a Schengen state, Monaco, Bulgaria, Cyprus