Each country has identification requirements for entry into their country. These requirements can vary in accord with the traveler's country of citizenship or with their mode of travel. For example, U.S. citizens do have the option of traveling to certain countries by land or sea without the use of a passport. When traveling to countries within the scope of the Western Hemisphere Travel Initiative, countries such as Mexico, Canada, Bermuda and the Caribbean region, U.S. citizens can use a combination of approved documents that satisfy the question of identity and citizenship, such as a driver's license, military-issued I.D. or state-issued I.D. alongside a birth certificate, Consular's Report of Birth Abroad or Certificate of Naturalization. However, when U.S. citizens travel by air, they must be in possession of a valid, unexpired passport in order to gain entry back into the United States.
Some countries will allow entry with a valid, unexpired passport only, while others require a passport and additional documents as well. Countries that allow American citizens a short-term stay with a passport alone (the definition of short-term varies with the country), include many in Europe, such as France, Austria, Belgium, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovak Republic, Slovenia, Spain, Sweden and Switzerland. Countries outside of Europe include Japan, New Zealand, Peru, South Africa and South Korea.
Many countries require a passport and visa for entry. A visa is a stamp, mark or electronic insert made on a traveler's passport by immigration authorities. It indicates that the traveler has permission to enter the country for a stay within a predetermined length of time and specified purpose. The specific purpose of the visit dictates the type of visa required. For example, a tourist or L visa is required for an American citizen wishing to visit China for sightseeing or visiting family members or friends or for other personal affairs, however a Business or F visa is required for "an alien who is invited to China for a visit, an investigation, a lecture, to do business, scientific-technological and culture exchanges, short-term advanced studies or internship for a period of no more than six months." Visas are standard for entry into many countries, including Australia, India, Egypt and Russia. You can obtain a visa by placing an application with the foreign country's consulate or embassy that is closest to, and has jurisdiction over, your place of residence.
