Travel visa

A travel visa (from Latin charta visa 'paper that has been seen'; also known as visa stamp) is a conditional authorization granted by a polity to a foreigner that allows them to enter, remain within, or leave its territory. Visas typically include limits on the duration of the foreigner's stay, areas within the country they may enter, the dates they may enter, the number of permitted visits, or if the individual can work in the country in question. Visas are associated with the request for permission to enter a territory and thus are, in most countries, distinct from actual formal permission for an alien to enter and remain in the country. In each instance, a visa is subject to border control at the time of actual entry and can be revoked at any time. Visa evidence most commonly takes the form of a sticker endorsed in the applicant's passport or other travel document but may also exist electronically. Some countries no longer issue physical visa evidence, instead recording details only in border security databases.

Some countries require that their citizens, and sometimes foreign travelers, obtain an exit visa in order to be allowed to leave the country. Until 2004, foreign students in Russia were issued only an entry visa on being accepted to University there, and had to obtain an exit visa to return home. This policy has since been changed, and foreign students are now issued multiple entry (and exit) visas.

Historically, border security officials were empowered to permit or reject entry of visitors on arrival at the frontiers. If permitted entry, the official would issue a visa, when required, which would be a stamp in a passport. Today, travellers wishing to enter another country must often apply in advance for what is also called a visa, sometimes in person at a consular office, by post, or over the Internet. The modern visa may be a sticker or a stamp in the passport, an electronic record of the authorization, or a separate document which the applicant can print before entering and produce on entry to the visited polity. Some countries do not require visitors to apply for a visa in advance for short visits.

Visa applications in advance of arrival give countries a chance to consider the applicant's circumstances, such as financial security, reason for travel, and details of previous visits to the country. Visitors may also be required to undergo and pass security or health checks upon arrival at the port of entry.

Uniquely, the Norwegian special territory of Svalbard is an entirely visa-free zone under the terms of the Svalbard Treaty. Some countries—such as those in the Schengen Area—have agreements with other countries allowing each other's citizens to travel between them without visas. In 2015, the World Tourism Organization announced that the number of tourists requiring a visa before travelling was at its lowest level ever.

The history of passports dates back several centuries, originating from early travel documents used to ensure safe passage across regions. One of the earliest known references to a passport-like document comes from 445 BCE in Persia, where officials were provided letters by the king for safe travel. Similarly, during the Han Dynasty in China, documents were required at checkpoints to verify travelers' identities. In medieval Europe, rulers issued "safe conduct" letters that protected travelers. In 1414, during the reign of King Henry V of England, passports became more formalized, allowing foreigners and citizens to travel safely within England. The 19th century saw an increase in international travel due to the Industrial Revolution, which led to the widespread adoption of passports, particularly for managing the movement of migrant workers.

In Western Europe in the late 19th century and early 20th century, passports and visas were not generally necessary for moving from one country to another. The relatively high speed and large movements of people travelling by train would have caused bottlenecks if regular passport controls had been used.

After World War I, passports and visas became essential for international travel. The League of Nations convened conferences in the 1920s to standardise passports, setting the foundation for modern versions. The International Civil Aviation Organization (ICAO) took over regulation in 1947, leading to machine-readable passports and, eventually, biometric passports in the late 20th century, offering enhanced security and speed in processing travelers.