Dublin Regulation (1997, revised 2003, 2013): “Migrants seeking to apply for asylum within the European Union must do so in the country through which they first enter the bloc. The country in which the asylum seeker first applies for asylum is responsible for either accepting or rejecting asylum, and the seeker may not restart the process in another jurisdiction.” (Wikipedia, New York Times, 20 September, 2015)
Schengen Agreement (1995): “Passport-free movement across most of the EU.” Applies to all EU states except Bulgaria, Croatia, Cyprus, Ireland, Romania and the UK. Non-EU states Norway and Switzerland are also part of the Schengen zone. (Wikipedia, BBC, 14 September, 2015)
"Frontex, the EU’s border force, swells in size"
(Economist, March 2021)