Nationals of European Economic Area Member States who are not nationals of the United Kingdom and Ireland have the right to enter and stay freely in Ireland (and had the same right in the United Kingdom, when he was a member of the EU). You must carry a valid travel document, passport or national identity card in order to enter the CTA and travel between Ireland and the United Kingdom.  The Common Travel Area (CTA) is an agreement between the United Kingdom (United Kingdom) and Ireland, which gives the citizens of these countries a large number of rights. It implies more than the fundamental right to travel freely between the two countries. The agreement obliges the two governments to continue their cooperation through the CTA, to align their lists of visa-free countries, to develop an electronic border management system,to participate in the joint use of data to combat the «abuses» of the CTA and to work towards the establishment of a «fully common visa for short-term stays».    Prior to the creation of the Land of Bavaria, British immigration legislation in Ireland was considered part of the United Kingdom. With Ireland`s independence in 1922, the British Home Office was not inclined to introduce passport and immigration controls between Ireland and Northern Ireland, which would have meant patrolling a porous and outdated land border of 499 km. However, if the situation were to continue before 1922, the Irish immigration authorities would have to continue to apply British immigration policy after independence. The Irish Ministry of the Interior was sensitive to the continuation of the status quo and, in February 1923, an informal agreement was reached on this issue: each party would apply the other party`s immigration decisions and the Irish authorities would receive a copy of the British Code of Suspects (or «Black Book») of non gratae for personal use in the United Kingdom.  The line of service providers from Switzerland will be open in December 2020 and is expected to continue until 31 December 2025. The itinerary allows authorized service providers to travel to the UK to execute a contract (s) (s) (s) (s) (s) (s) (s) (s) for up to 90 days per calendar year.
The CTA was suspended at the outbreak of war in 1939 and travel restrictions were introduced between the islands of Great Britain and Ireland.  This meant that travel restrictions even applied to persons travelling within the United Kingdom when travelling from Northern Ireland to other countries in the United Kingdom. In 2011, the first public agreement between the British and Irish governments on the continuation of the CTA was reached. It was officially signed on 20 December 2011 in Dublin by uk Immigration Minister Damian Green and Irish Justice Minister Alan Shatter.  At the same time, the two ministers also signed an unpublished Memorandum of Understanding.  Protocol 20 attached to the EU treaties provides that the United Kingdom and Ireland can maintain their specific common travel regimes. In particular, it facilitated the continuation of the opt-out in the Schengen agreements. The main legislation on Schengen visas and common schengen immigration control does not apply. The Common Travel Area (CTA); The Irish territory of Comhlimistéar Taistil is an open border territory that includes the United Kingdom, Ireland, the Isle of Man and the Channel Islands. British overseas territories are not included. On the basis of agreements that are not legally binding, the internal borders of the CTA, if any, are subject to minimal controls and can normally be overtaken by British and Irish citizens whose identity documents are minimal, with some exceptions.
  The continuation of the CTA implies cooperation between the British and Irish immigration authorities. Ireland and the United Kingdom today (20 December 2011) signed a landmark agreement reaffirming their commitment to preserving the Common Travel Space (ATC) while continuing to fight illegal immigration and false asylum claims.