This article describes concerns about border crossing. See interesting borders for borders as an attraction.

National borders appear very different from each other. While closely associated countries such as the Netherlands and Belgium might be divided by a mere line in the pavement, borders with much political tension might be heavily fortified, such as the Korean DMZ.

In general, there are three kinds of border controls: Immigration, which checks people crossing the border, Customs, which checks goods crossing border and Security, which is for the safety of the aircraft or vehicle used to make the trip. For purposes of conducting border controls, the international sections of airports and seaports may also be classified as borders. Depending on the political situation and sometimes the mode of travel, none, one, or all may be enforced.

In addition to borders between proper countries, there may be borders or control points inside what could be regarded as one country. Greenland, although part of the Kingdom of Denmark, maintains its own immigration policies, and agricultural checks are carried out when travelling between mainland USA and Hawaii.

See also: Passport, Visa, Visa trouble, Traveling with a criminal history

The terms for travelling between countries differ a lot. The destination country's embassy in your homeland, or their foreign affairs department, can provide information for their country. While travel agents' homepages might inform about rules for their destination country, there is no guarantee that the information is up to date. As a general principle, rules are more relaxed for citizens of a high-income country who visit a low-income country, than the other way around. For tourists who make a temporary visit, without the intent to settle or work, there are some typical cases:

1. No check at all. Carrying a passport or other appropriate ID is still recommended when travelling abroad. If you carry goods that need to be declared, you must go to the customs unprompted.
2. Selective passport check.
3. Passport check, possibly stamping of passport.
4. Passport check and a standard questionnaire on arrival, usually on a document provided by the carrier. If the questionnaire is approved, you get a temporary visa to stay in the country.
5. Visa on arrival. In practice the same as the above, except that you pay for the visa.
6. Electronic travel authority (ETA). Similar to visa on arrival, except you provide your details, complete the questionnaire and pay the fee several days before your flight.
7. Advance visa application. Some visa processes can be done online. Others might be complicated, requiring a physical visit at the destination country's embassy. A visa gives no guarantee to enter the country.

If you have a criminal record or have pending legal proceedings against you, some countries might deny entrance, or require special assurance.

A visa or entrance permit might require a return ticket, documentation on sufficient funds, an address to the accommodation, and statement of the journey's purpose. It is usually limited in time; often a maximum of 90 days.

Entry to a country may require documents on vaccination. Also pets may need documented treatments (typically at least rabies vaccination).

Permission for studying abroad, working abroad or retiring abroad usually requires a special visa or permit. Some countries have questions that may intrude on your privacy, such as about your political history, employment, economic status, and previous addresses.

Some countries' customs control have a form for you to fill out, stating such things as what goods you are planning to leave in the country or how much cash you carry. In some countries it is required, in others you should get the form and get it stamped if you carry money or valuables out of the ordinary, to avoid problems when customs finds them, possibly on your way out. See also Proof of what you already own.

Some items may be banned or require paperwork to import. You don't want to be told at the border that your pet should have got that tapeworm cure in advance, or that your sealskin purse will get you to court.

Some border crossing points are open only at specific hours. Check this beforehand.

Changes of time zone usually happen at national or regional borders. Double check which one is used in any timetable, mind the missed or added hour (or hours) and don't count the wrong way.

See also: At the airport#Security check

Security checkpoints differ between forms of transport, and countries involved. For flights this obviously involves extensive checks on any potentially dangerous items, it is as strict as to include bottles of liquid, pocket tools and laser pointers. Be aware of sniffer machines; make sure you have a shower and change your clothes after going hunting or being on the firing range.

On vehicle ferries there are often chemical and radioactive material scanners you need to drive through. Some crossing vehicles may be quickly checked inside looking for stow-away illegal immigrants.

Road border security may be nothing more than just slowing down a little. Although there are no physical checks, there are usually cameras scanning vehicle number plates and sometimes facial recognition scans.

While most trains have no security check, Eurostar (between England and mainland Europe) and Chinese high speed trains do, so plan arriving half an hour or so early at the station.

At high-risk destinations, an airport or transportation terminal might have multiple security checkpoints. They can be at the road gates, at the building entrance, and at the airside barriers.

Buses rarely have security checks, but on some routes you might have to pass through a metal detector or have your bags scanned.

An immigration checkpoint is usually the first stop when disembarking from a plane, a ship, or another vehicle. In some cross-border trains inspections are done on the running train and you should have valid ID with you when boarding one of those trains. On night sleeper trains, passports may be collected by the conductor so that you do not have your sleep interrupted.

Here checks are made to see that you are allowed to enter a country. This will involve checking that your travel documents are correct and perhaps asking you some questions about your travel plans. Common questions, which you should be ready to answer when entering a new country, include the reason for entering the country (tourism, business, work, etc.), the length of your stay, the address of your lodging, and the details of how you plan to leave. What further questions you will have to answer and how you are processed will depend on whether you are travelling just as a short term tourist, for work (short or long stay), study, emigration or seeking asylum. Checks may also be made on any criminal and political history (see travelling with a criminal history). At some borders evidence of travel to some countries (however circumstantial) may make you subject to further questioning or being denied entry altogether. Similarly, visa-free entry or electronic visas like the US visa-waiver program may be restricted if you've visited certain countries in the past. Some countries can deny entry if your motive for travel or explanation of your trip seems dubious or questionable; religion and sexuality are also areas that may be treated with suspicion by some countries; some countries require enough economic funds, by some definition. Having only a one-way ticket may be questionable or forbidden without a proper visa. In some cases documents may be required, such as a copy of your hotel reservation, your ticket out of the country, a bank statement showing sufficient funds, vaccination certificates (especially for yellow fever), an invitation letter, or an extra passport photo.

Most countries also require you to go through immigration checks when you leave, the most notable exceptions being the United States, United Kingdom and Canada. This is usually relatively uncomplicated, though you may be prevented from leaving the country if you are wanted for a crime for instance. In addition, there might also be checks to ensure that you are not trying to smuggle anything out of the country illegally.

Some countries, such as the United States, China, Japan, South Korea, Taiwan and Singapore require all visitors to be fingerprinted by immigration on entry. While this may be controversial due to privacy concerns, you are expected to cooperate with the authorities on the matter rather than insisting on your right to privacy. If you refuse, expect to be barred from entry into the country and placed on the next flight out.

A few isolated territories, such as Svalbard or Antarctica, have no border controls, or legal or de facto restrictions on immigration. However, they might only be within reach through countries with border controls; for instance, all regular flights to Svalbard depart from Norway. Some territories might require permission by a relevant government agency; for Antarctica the permission can be obtained by any signatory country of the Antarctic Treaty.

See also: Shopping#Restrictions

The customs takes care of your paying duties and taxes on your imports and making sure you're not importing – or exporting – illegal goods. Often there is a customs checkpoint at the border crossing (or at the gate of a free port) for this purpose. Sometimes the customs office is elsewhere and you need to go there unprompted if you carry any restricted goods or something you need to declare. Also in the latter case, there may be checks at random or when there are suspicions of smuggling. Sometimes sniffer dogs are used to find drugs and other goods that interest customs. Also vehicles can be searched for illegal stowaways.

Restricted goods typically include drugs (including some ordinary medicines), foodstuff, alcohol, tobacco and nicotine products, firearms and hunting trophies, products from protected animals and antiques. Pets may need ID documents and documented treatments, some are not permitted at all. There may be taxes on anything you might want to sell, beyond normal travel equipment. Often you need to declare imports and exports of large sums of money or valuables out of the ordinary.

In many countries, customs is very strict on illegal drugs, including coca, cannabis and some e-cigarette liquids. Some customs sniffer machines are very sensitive, so do not eat a poppy seed coated bread roll (opiates are made from poppies and most drug tests give false positives after consumption of poppy seeds) in Frankfurt Airport before a flight to the Gulf countries.

To prevent the transfer of disease, food stuffs and plant products are generally not allowed to be transported across borders; this can and often does include things like the apple in your bag or firewood in your truck.

Some countries prohibit travellers from bringing in items from particular countries; many Arab countries prohibit bringing in products of Israel, while the U.S. prohibits bringing in most products from countries on which it has imposed economic sanctions (Iran and Cuba) – and exporting things such as certain high tech, which may be software of your computer.

One problem is software and files forbidden at your destination, or software that may not legally be exported to there. This may include high-tech such as cryptography software and software that circumvents restrictions, such as DVD players on Linux. Also files regarded as pornography and propaganda (by the country's definitions, in the worst case even if just in already "deleted" temporary files) can cause severe problems.

Governments are increasingly snooping through data stored on mobile devices, a problem for business travel as many professionals are bound by ethical, contractual or legal restrictions to keep certain data (such as lawyer-client, journalist-source, preacher-parishioner or doctor-patient communication) privileged or confidential. Voyagers have been turned away at the border because data on their mobile devices indicated their intention to engage in peaceful protest while in the USA, depicted video of Muslim prayers or contained names of people the government dislikes among the contacts. Non-citizens at a border post typically receive none of the rights that a nation is expected to extend to its own citizens at home. It may be best to carry a "burner" phone with no sensitive data, passwords or encryption keys in the device's local memory.

Some customs-like inspection points are not related to international borders. For example, all travellers to and from Hawaii (and on many overland routes into California) are subject to a rather comprehensive agricultural inspection, whereas most borders between EU countries don't have any customs inspections in the classical sense at all.

You may well get picked out for spot checks, even well after crossing the border, if arriving from e.g. the Netherlands and fitting certain criteria.

Some countries conduct customs checks when you leave to ensure you are not exporting anything that is forbidden. An example is China, which prohibits antiques from 1911 or early from being exported.

If you have goods that need customs clearance and the border is less strictly checked (such as between Finland and Norway – or Åland!), you may have to visit a customs office quite a distance from your intended border crossing, possibly open only at specific hours (daytime, office hours or at ferry arrival).

Security controls are obviously done before boarding the form of transport. In airports and other transportation terminals, customs is usually the last checkpoint after baggage claim and duty-free shopping, before legally entering the destination country. Sometimes border controls are carried out on both sides of the border, by the respective country.

Immigration and customs may not be directly on the border. For example, British passport and customs control for cross channel ferries and Eurostar are on the French side before boarding (and French controls are on the British side); and for flights to the USA from Canada, the US controls can be at the Canadian airport (the same goes for some airports in Ireland, UAE and the Caribbean too). The check can also be some distance from the border itself, e.g. at the start of a border zone, to avoid contact between officials of hostile countries, or by the village closest to the border, where there is infrastructure. An example is Knunjerab Pass, where Chinese and Pakistani immigration and customs inspection will be done far away from the border itself (However, preliminary screens will be conducted at the border).

At some laid-back land border crossings, including towns on the Brazil-Uruguay border, the checkpoint may not be obvious or even close to the border. In that case you might have to proactively find it to make sure your entry or exit is registered correctly; if you don't, you could wind up in trouble later for illegally entering the new country or for overstaying if the old country didn't register your departure (and similarly for not declaring imports).

In some cases, immigration control is also imposed on domestic travellers; people travelling between Peninsular Malaysia and East Malaysia, as well as between the East Malaysian states of Sabah and Sarawak, are subject to immigration controls, as are travellers between Iraqi Kurdistan and the rest of Iraq, as well as those traveling between the Special Administrative Regions of Hong Kong or Macau and Mainland China.

Customs controls may also occur where there is no national boundary, such as on entering and leaving a free port area, or within a country, for example Germany frequently checks vehicles (particularly foreign trucks) on their autobahns.

Customs-like controls are in place for people and goods travelling between different Australian states (and sometimes into specific regions within each state), and sometimes into specific agricultural regions within the United States (including controls on those travelling between the mainland and Hawaii).

Free movement

[edit]

Some (typically neighboring) countries have agreements that allow travel between them without having to pass immigration.

There is full free movement among all European Union countries, Iceland, Norway, Liechtenstein and Switzerland, although passports may be required when crossing borders. The Schengen agreement allows travel between many European Union and EEA countries even for non-citizens without any border checks in normal circumstances. Citizens do not need a passport if they have an official ID card (and not even that in some cases). Visiting customs or making arrangements may still be necessary in special cases (e.g. bringing a pet, carrying firearms, having a country-specific visa).

The United Kingdom and Ireland, which are not members of Schengen, have a separate mutual free movement treaty, still in force even after the UK exited the European Union. The terms of Britain’s exit from the EU may require the UK to implement customs checks for domestic UK travel between Great Britain and Northern Ireland.

The Central America-4 (CA-4) Border Control Agreement is a treaty between the Central American nations of El Salvador, Guatemala, Honduras and Nicaragua that allows the free movement of citizens and foreigners (with a valid visa for one of those countries).

The Russia-Belarus Union State allows Belarusian and Russian citizens free movement similar to that which exists with the UK and Ireland. This is not the case for other foreigners, as it is not possible to travel between Russia and Belarus overland. The only way to travel between them for foreigners is by air, where they will go through normal immigration and customs inspection.

The member states of the Gulf Cooperation Council (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates) allow their citizens freedom of movement inside the area. However, this does not apply to foreigners and even holders of a tourist visa to one of the GCC countries will have to submit to Saudi Arabia's pretty strict visa requirements even for a short visit.

The Mercosur trading bloc in South America functions as a customs union, similar to the European Union in that it allows unencumbered trade between member states with common external tariffs, and free travel, residency and work for nationals of member countries. The name is a Spanish portmanteau of Southern Common Market, rendered in Portuguese as Mercosul. Its members are Argentina, Bolivia, Brazil, Paraguay, Uruguay and Venezuela (membership suspended since December 2016). In 2023, their combined GDP of US$5.7 trillion placed the bloc as the 5^th largest economy in the world. Many South American countries accept photo ID for travel in the region for South American citizens. Panama announced its intention to apply for Associate Membership in July 2024, which if granted, would represent the group's first expansion outside South America.

Citizens of Australia and New Zealand have freedom of movement between each other's countries, though they still have to pass through customs and immigration, and this privilege can be revoked for those who have a criminal record. However, this does not apply to foreigners, who need to meet the visa requirements for each country they wish to visit.

The African Union Passport was unveiled in 2016 that will (in theory) allow all citizens of all 57 African nations visa free travel around the continent. It remains to be seen how quickly this will be adopted by member states.

Citizens of the ASEAN group of countries in South East Asia can travel visa-free around the bloc (with the exception of Malaysia and Myanmar; both still require visas for citizens of the other). However, full border controls remain in place, and ASEAN citizens are not allowed to take up residence or work without permission in another ASEAN country.

See also: Arriving by plane

The airside of some international airports is a no man's land, where arriving passengers don't need to pass Immigration or Customs; however, Security might be enforced.

Some countries enforce immigration control even for transit passengers; notably the United States and Canada. See Avoiding travel through the United States and Canada to find other ways around the world.

Some countries, such as the USA, charge for immigration control costs. For air travellers this may be hidden in the price of the ticket, but if you cross by car or on foot, you will have to pay directly. In some (particularly low income) countries you will have to pay a fee even if arriving or leaving by air and this fee isn't included in your ticket price or comes on top of the fees that are. Such fees or taxes are charged for a variety of purposes, including to cover administrative costs, for environmental reasons, to discourage air travel, or to raise general funds. At some borders these fees can be paid by any variety of means (either currency or even a third one as well as credit and debit cards) whereas others insist on it being paid in national currency and small change. It is also common for immigration officers in poorer countries to demand bribes on top of the official fee.

Even if there are no official fees, border officials in some developing countries may demand a bribe before letting you into the country or allowing you to leave. Wikivoyage aims to cover these things in the Get in sections of country articles and border destinations, but if you see something that we don't or that is out of date, plunge forward.

See also: Returning home

If your passport is in order, immigration is typically a smooth formality when you return home.

Customs checks might be more harsh, however, especially if you arrive from a country associated with smuggling or other illegal border activity.

• North America: Avoiding travel through the United States, Avoiding travel through Canada, Global Entry, NEXUS, Americans in Cuba
• Europe: Travelling around the Schengen Area, Visa summary for EU citizens

See also: Interesting borders

Travel should be fun, including the border crossings, where you may get a passport stamp to celebrate your arrival, and where officials are mostly welcoming to prosperous law-abiding visitors. Bearing in mind that things change, not necessarily for the worse, here are some borders that have been especially agreeable to cross in the early 21st century:

• Baarle in Belgium, or is it in the Netherlands? The Belgian border takes some strange twists and turns, and at Baarle it excels: it's as if a map of the Belgian section of town was etched on glass then dropped. There are shards of Belgium within the Netherlands, and vice versa, sometimes within the same building. Cobbles mark the border and the main issue for visitors is different pub rules: police on each side have little else to do but usher transgressors back across the cobbles to where their behaviour is legal.
• Vatican City has just a low chain fence dividing St Peter's Square from the City of Rome in Italy, easily stepped over. (The other entrances, e.g. to the Vatican Museum, aren't so distinctive.) Street drinking offences aren't a factor unless you've got in with an unusually bibulous set of Cardinals. But contemplate the long centuries in which the Papacy was a temporal power, with similar sanctuary lines drawn across many Italian city-states.
• Nicosia between Greek and Turkish sectors of Cyprus: the Ledra Street pedestrian crossing is within a bazaar. You might even struggle to locate it among the cafes and piles of cheap jeans, until you realise that the fellow getting in your face really does need to see your passport, he's not offering "free coffee and halva, please step in no obligation to buy". The vehicle crossing is more convenient for the must-see museum but is more like a parking lot entrance, just a metal bar across a potholed lane.
• Panmunjom in South Korea, or is it North Korea, is where the 1953 armistice was signed. It's now a visitor attraction with the treaty conference rooms and table straddling the border. You can visit from either side, and hop across the border within the confines of one of the conference rooms, with soldiers blocking the exit to the other side. What those guards want most is a smart quiet watch, with no paperwork or reprimands for incidents, so help them to help you and keep moving around the room and out.
• Canusa Street runs along the border between Stanstead in the Canadian province of Quebec and Beebe Plain in the U.S. state of Vermont. This means that crossing the street will result in you ending up in a different country. However, this is no longer allowed since 9/11, and you now have to report to border control at the western end of the street if you want to cross it. The Haskell Free Library and Opera House straddles the border, and you can freely hop across the border while inside the building. Although the entrance is on the American side, visitors from the Canadian side may cross the border to immediately enter the building without passing through border control as long as they follow a specific path.
• Chung Ying Street, literally "Sino-British Street", runs along the border between Sha Tau Kok in Hong Kong and the district of Shatoujiao in Shenzhen, mainland China, meaning that one side of the street is in Hong Kong (that used to be British), and the other in mainland China. As the Hong Kong side is within the Frontier Closed Area, only Sha Tau Kok residents are permitted to visit from the Hong Kong side. All Chinese citizens may visit from the mainland Chinese side provided they obtain a permit in advance, but this permit is not available to foreigners.
• The road between Värska and Ulitina passes through Russia even though both ends of the road are located in Estonia, a legacy of the time when both were part of the Soviet Union. No Russian visa is required to drive or cycle on this road, though you are required to drive or cycle continuously and may not stop or walk while inside Russia, and you may also not leave the road to travel to the rest of Russia.
• Madha is an exclave of Oman surrounded entirely by the United Arab Emirates, which in turn surrounds the enclave of Nahwa which belongs to the UAE.
• Up a lazy river: there's just something about river border posts. A good example is the Mekong river ferry between Vietnam and Phnom Penh in Cambodia, where the boat draws in to the mudbanks and you skitter on planks up to the border station. Picture palm trees, louche officialdom, and a ceiling fan turning lazily.
• Keinovuopio, the northernmost permanently habited place in Sweden, has no road from the rest of the country, just a pedestrian suspension bridge from Finland (where a highway passes by) over the border river. No official border crossing here, but who cares?
• Traffic switch, when a drive-on-the-right country meets a drive-on-the left – somewhere between them is a mixture of dodgems and wacky races. Examples are Thailand with Laos, Cambodia and Myanmar, Pakistan with China, Iran and Afghanistan, and mainland China with Hong Kong and Macau. Regimental histories gloss over this point, but one of the dangers of the Khyber Pass was the Torkham traffic switch on the Pakistan-Afghanistan border.
• Wagah-Attari, the main crossing between India and Pakistan, is only open until sunset, when there's an elaborate military closing ceremony. Tattoo? – it's almost camp. Join the onlookers in the bleachers if you can.

These we have lost: the DDR – West Berlin border so long as you had a western passport and money in your pocket. Checkpoint Charlie is the best known but even more curious was Checkpoint Friedrichstrasse, with metro platforms and trains for both east and west city networks separated by five lethal metres of track.

• Carnet de passage
• Diplomatic missions
• Duty-free shopping
• Passport
• Visa
• Visa trouble
• Common scams#Border crossings