There is a space on earth where borders are virtually removed between a cluster of countries. It's called the European Union, a space 3,000 km wide in which 500 million people live. More than anyone would need. Within that space, a citizen of one country can leave his village, travel many kilometers, cross many borders and settle down wherever he thinks the grass is green enough. He can get a job if he feels like it, claim government support, mingle with the local society or keep to himself... his status of immigrant will barely hinder his possibilities.