Some use words such as "horrific" and "devastating" to describe the prospect of an end to the 30-year-old Schengen accord, seen one of the essential linchpins of post-World War Two peace and prosperity in Europe. Now stretching from Greece in the south to Iceland in the north and encompassing more that 400 million people, the Schengen area has offered border-free commercial and personal movement since an initial 10-nation pact in 1985. It has been widely considered one of the European Union's most successful, wealth-creating projects, stretching to several non-EU countries and excluding just Britain and Ireland in Western Europe.