In December 1996, two non-EU states, Norway and Iceland, signed an association agreement with the countries that signed the Schengen accession agreement. Although this agreement never entered into force, the two countries were part of the Schengen area following similar agreements with the EU.  The Schengen Agreement itself was not signed by non-EU states.  In 2009, Switzerland officially concluded its accession to the Schengen area by adopting an association agreement by referendum in 2005.  European integration has created a “mixed policy” in a world of states. Mixed political status gained new quality with the Amsterdam Intergovernmental Conference, which helped to confer quasi-constitutional status on the concept of flexibility. With regard to the role of constitutionalism in this mixed policy, it has been argued that Amsterdam offers new ideas on the role of the law. Neil Walker pointed out: “Amsterdam is both instrumental and reflexive. It contributes to unforeseen architectural flexibility, especially in the documentation of recent compromises on Schengen and the third pillar, and begins to reflect on certain principles of design and order, to learn from them and to impose certain principles of order… ” (Walker, to come, p. 4).
The Schengen Agreement was signed on 14 June 1985 by five of the ten EC Member States in the Schengen City, Luxembourg. The Schengen area was created separately from the European Communities, when not all the Member States of the Eu reached a consensus on the abolition of border controls. A short-stay visa costs 60 euros (46 USD; 66 USD) but only 35 euros for Russians, Ukrainians and citizens of some other countries, as part of the facilitation of issuing visas. After Slovakia, Denmark, the Czech Republic and Poland announced in mid-March the complete closure of their national borders, European Commission President Ursula von der Leyen said that “some controls may be justified, but the World Health Organization does not consider general travel bans to be the most effective. In addition, they have strong social and economic repercussions, disrupting people`s lives and affairs across borders.  Von der Leyen also apologised to Italy, amid widespread Italian discontent over Europe`s lack of solidarity.  Until the end of March 2020, almost all of Schengen`s internal borders were closed to non-essential travel. By July 2020, most of the borders closed due to coronavirus had been reopened. The Schengen Agreement was signed independently of the European Union, partly because of the lack of consensus among EU Member States on whether the EU is responsible for removing border controls and, secondly, because those who were willing to implement the idea were not waiting for others (at that time , there was no enhanced cooperation mechanism). The agreement provided for a harmonization of visa policy allowing people in border areas to cross the borders of fixed checkpoints, replace passport controls with visual surveillance of vehicles at reduced speeds, and carry out vehicle checks allowing vehicles to cross borders without stopping.
 The additional obligations imposed by European law on national border authorities with regard to the treatment of third-country travellers (for example.B.