For U.S. citizens, there are very few "foreign" countries you can visit without a passport, but there are several destinations that feel international. You can travel to U.S. Territories such as Puerto Rico, the U.S. Virgin Islands (St. Thomas, St. John, St. Croix), Guam, and American Samoa without a passport; a standard government-issued photo ID is sufficient. Additionally, U.S. citizens can enter Canada and Mexico by land or sea using a "Passport Card" or an Enhanced Driver's License (EDL), though a full passport book is still required for air travel. For citizens of the European Union, the Schengen Area allows travel between 29 European countries without a passport, using only a national ID card. Similarly, the Common Travel Area allows British and Irish citizens to travel between the UK and Ireland without a passport, though airlines often require some form of photo identification for the flight itself.