The expansion of the European Union towards east in 2004 enabled any German wishing to live and work in Poland, and thus east of the Oder–Neisse line, to do so without requiring a permit. German expellees and refugees became free to visit their former homes and set up residence, though some restrictions remained on the purchase of land and buildings. Poland entered the Schengen Area on December 21, 2007, removing all border controls on its border with Germany.