Airports that span multiple nations

International travelers in the age of Covid face the challenge of navigating a constantly evolving landscape of rules and travel restrictions.

To avoid potential quarantine delays, ensure your travel documents are up to date before crossing any border—especially if you’re flying into airports where it's easy to accidentally end up in the wrong country.

The airports listed below, or parts of them, are operated jointly by more than one nation, adding a unique twist to the concept of an 'international' airport.

Euroairport Basel-Mulhouse-Freiburg (BSL)

Euroairport Basel-Mulhouse-Freiburg (pictured above) is a rare example of an airport designed from the ground up as a bi-national facility.

Nestled at the point where the borders of France, Switzerland, and Germany converge, Euroairport serves three cities: Basel (Switzerland), Mulhouse (France), and Freiburg (Germany). Basel is the largest and closest city to the airport, which is reflected in its IATA code, BSL.

Although the airport is technically located within France, Switzerland benefits from certain extraterritorial rights under a special bilateral agreement, making it, in many respects, both a Swiss and French airport. Since the 1980s, German officials have also had a role in some of the airport’s governance bodies.

In practice, the airport is divided into French and Swiss sectors, with a physical boundary running right through the terminal. Each sector has its own customs and border control, with officers from the respective countries.

Despite this division, the airport is still considered French sovereign territory, with French law enforcement overseeing overall security operations.

Switzerland's entry into the EU’s Schengen visa zone eased the border divide, and since 2008, passengers have been able to move freely between the French and Swiss sectors of the terminal.

Most services within the terminal are tailored to either the French or Swiss side, depending on which part of the airport you’re in.

Shops and cafés in the French sector accept euros, while those in the Swiss sector use Swiss francs (with corresponding prices and brands matching their respective countries). Though rarely seen today, phone booths and postboxes once symbolized the national divide as well.

Travelers bound for Switzerland can access Basel via a special road that cuts through French territory but remains free of border checks, as it falls under a bilateral agreement allowing Swiss urban buses to reach the airport directly.

The unique cross-border arrangements were recently tested during the pandemic when France and Switzerland imposed different Covid entry requirements. At times, France required testing, while Switzerland did not, opting instead for quarantines. To handle this, Swiss-bound travelers were physically separated during these measures.

“We serve as a living example of cross-border collaboration,” says Claire Freudenberger, the external communications manager at Euroairport, in an interview with Dinogo Travel.

Geneva (GVA)

Geneva Airport, formerly known as Cointrin, is situated entirely on Swiss soil, although its runway edges almost touch the French border. The unusual right-angle turns along the airport's boundary are not coincidental, but a result of the border’s unique path.

In the 1950s, when Swiss authorities sought to extend the airport's runway, the only viable option was to extend it over French land.

This issue was resolved through an international treaty, in which France and Switzerland exchanged land of equal size. Switzerland was allowed to expand the runway, while France was granted use of a section of the airport.

The “French sector,” connected to mainland France via a dedicated road, enables French passengers to fly to Paris and other destinations without having to clear Swiss customs.

Although the entire airport remains under Swiss sovereignty, businesses in the French sector operate using euros and apply French sales tax.

While Switzerland is part of the Schengen Area, it is not in the EU customs union, meaning French customs are also present at the airport terminal.

A joint committee, with top officials from both countries, convenes at least once a year to address any issues related to these cross-border arrangements.

“Currently, the French sector has just four boarding gates, which can occasionally create some limitations,”

“Switzerland’s inclusion in the Schengen Area has opened up new opportunities; for instance, we’re exploring the possibility of shifting from a physical French sector to a more flexible, operationally-driven model based on airport needs,” says Gael Poget, director of international and governmental affairs at Geneva Airport, in an interview with Dinogo Travel.

Cross Border Xpress (CBX)

While the US-Mexico border wall has been widely covered in the media, fewer people know that at one point, you can actually walk over it—if you have a boarding pass in hand.

Gibraltar International Airport (GIB)

While the previous airports on this list highlight successful international cooperation, Gibraltar stands out as a much more controversial case due to the ongoing sovereignty dispute between the UK and Spain over this British Overseas Territory.

Gibraltar's airport was constructed just before World War II, situated at the edge of Gibraltar's isthmus, only meters from the Spanish border, on land that Spain argues was not part of the Treaty of Utrecht, which ceded the Rock to Britain.

In 2006, during a temporary warming of relations under the Cordoba Agreement, the UK and Spain agreed that Gibraltar’s new airport terminal would be accessible from the Spanish side, and there were even discussions about forming a joint venture to operate some airport services.

However, none of these plans came to fruition. Only the British side of the terminal was finished (it opened in 2012), so passengers coming from Spain must cross the main border to reach the airport.

The territorial dispute also extends to Gibraltar's airspace, with Spain blocking its inclusion in the proposed European Single Sky initiative. While direct flights between Gibraltar and Spain are possible, they require bilateral agreements between the UK and Spain. Iberia, Spain’s national airline, operated a Gibraltar to Madrid route for a few years before it was discontinued in 2008.

“Given the current state of Brexit and the UK’s exit from the European Union, the Cordoba Agreement may no longer hold, as new arrangements are being considered between Gibraltar, the UK, Spain, and the EU. However, these talks are still in the very early stages,” a source at the airport tells Dinogo Travel.

US airports along the Canadian border

Several airports are located along the northern US-Canada border, straddling both countries.

When the US and Britain agreed on the 49th parallel as the official border between the US and Canada in 1846, they could never have predicted the future rise of the aviation industry and its impact on the border region.

The world’s longest uninterrupted border line cuts through the grounds of six airports, stretching from the Great Lakes to the Pacific Ocean.

To be honest, calling these airfields ‘airports’ is a bit of a stretch, as most consist of little more than a dirt runway in the middle of the prairies. Nevertheless, they still function as ports of entry and are subject to the formalities of international travel.

Let’s take a look at their locations, from west to east.

Avey Field, Washington

Despite having only four permanent residents (according to the 2020 US Census), the tiny settlement of Laurier, Washington, boasts its own ‘international’ airport.

The fact that the end of its gravel runway extends 500 feet into Canadian territory ensures that a significant portion of the 800 aircraft movements at Avey Field are considered international flights.

Customs facilities for both the US and Canada are located right next to the runway.

Del Bonita/Whetstone International Airport, Montana

This airport is part of a series where unpaved runways literally straddle the border line.

Del Bonita/Whetstone International Airport is owned and operated by the state of Montana, and is also accessible from the Canadian side.

A customs checkpoint is situated at the western edge of the airfield.

Coronach/Scobey Border Station Airport, Montana

Here’s another runway that runs directly along the border. The Coronach/Scobey Border Station airfield should not be confused with the nearby Scobey 9S2 airport, which is a few miles south and features a paved runway.

This airport is recognized as an official port of entry by Canada, although the mere 10 operations it handled in 2019 hardly keep the staff at the nearby border post busy.

Coutts/Ross International Airport, Montana

The unpaved runway at Coutts/Ross airport is accessible from both the US and Canada, as the border cuts right through the middle of the airfield.

Traffic at this airport is very light, with fewer than a dozen aircraft movements recorded in 2019.

International Peace Garden Airport, North Dakota

Named after the nearby International Peace Garden, established in 1932 to honor US-Canada relations, most of International Peace Garden Airport, including its runway and main facilities, is located on US soil.

Part of the apron extends into Canadian territory, allowing aircraft to operate both to and from Canada.

Piney-Pinecreek Border Airport, Minnesota

The name Piney-Pinecreek reflects the airport's shared use by the towns of Pinecreek, Minnesota, and Piney, Manitoba.

In contrast to its neighboring airports, this one features a paved runway that originally stopped just short of the border. However, in the 1970s, the runway had to be extended to accommodate larger aircraft, causing the airport to expand northward. With the southern boundary already defined by an existing road, this expansion ultimately turned it into a binational airport.