Europe’s border-free zone expands

The Schengen agreement, which allows passport-free travel across the area, now embraces 24 nations. The Czech Republic, Estonia, Hungary, Latvia, Lithuania, Malta, Poland, Slovakia, Slovenia joined the zone.

For non-EU nationals, a Schengen visa allows travel across all the participating countries.

Thirteen existing EU states have already been part of the Schengen accord as well as two non-EU countries, Norway and Iceland.

The UK and Ireland are not involved in the zone – which embraces 400m people – but they have signed up to agreements on security.

A significant element of the Schengen agreement is the Schengen Information Service (SIS) which features an enormous database in the French city of Strasbourg.

The SIS database enables police in any Schengen state to find out whether a suspect has been involved in any kind of crime across the EU.