Andorra population 80,000 (2013) is the sixteenth smallest principality in the world. For over 1000 years it hasn't had an army. It has no airport, no national bank and no income or sales tax.  It uses the euro as its currency. Tourism, the mainstay of Andorra's tiny, well-to-do economy, accounts for roughly 80% of GDP. An estimated 9 million tourists visit annually, attracted by Andorra's duty-free status and by its summer and winter resorts.  

For 715 years, from 1278 to 1994, Andorrans lived under a unique co-principality ruled by the French chief of state and the Spanish bishop of Urgel. In 1993, this feudal system was modified with the titular heads of state retained, but the government transformed into a parliamentary democracy. Long isolated and impoverished, mountainous Andorra achieved considerable prosperity since World War II through its tourist industry. Many migrant workers (legal and illegal) are attracted to the thriving economy with its lack of income taxes. (Wikitravel.org)