The World’s Shortest Borders, From a 150-Metre Line on the Zambezi to Monaco

The shortest border between two countries is the one between Botswana and Zambia at Kazungula, roughly 150 metres of the Zambezi River squeezed between Namibia and Zimbabwe and now crossed by the 923 m Kazungula Bridge. Next, according to Wikipedia's list of land borders, comes the 196 m line across Passport Island between Saudi Arabia and Bahrain, then the 1.2 km frontier between Spain and the British territory of Gibraltar, the 1.28 km line across Hans Island between Canada and Greenland, the 3.2 km boundary of Vatican City and the 4.4 km border of Monaco. If single segments count rather than whole borders, the record goes to the 75–85 m isthmus joining Spain's Peñón de Vélez de la Gomera to Morocco. Some of these short borders are the ones everyone expects; others are islands, causeways and exclaves that rarely make it onto a list.

Botswana and Zambia at Kazungula: about 150 metres of the Zambezi

At Kazungula, about 70 km west of Livingstone, four countries almost meet. Namibia's Caprivi Strip ends at Impalila Island, Zimbabwe lies immediately to the east, and the Chobe River, which divides Namibia from Botswana, enters the Zambezi. For decades the question was whether the four met at a single quadripoint or whether Botswana and Zambia touched along a short line. Shifting river channels and the absence of any agreement before 2000 left it unclear. It is now accepted that there are two tripoints joined by a line roughly 150 metres long; Wikipedia's border list gives 155 m and the bridge's own article 135 m.

That sliver mattered because it allowed a direct crossing that avoided both Zimbabwe and Namibia. For years the only link was the Kazungula Ferry, and in 2003 an overloaded Zambian truck capsized one of its pontoons, drowning 18 people. Botswana and Zambia announced a bridge deal in August 2007, construction began in late 2014, and the US$259.3 million road and rail bridge, built by South Korea's Daewoo E&C, opened on 10 May 2021. It is 923 m long and 18.5 m wide, with a single railway track between its two traffic lanes, and it is deliberately curved to avoid the nearby borders of Zimbabwe and Namibia. Even that was contested: in 2014 Zimbabwe's transport minister told parliament that Botswana and Zambia had no direct border at all.

Gibraltar, Vatican City and Monaco: the short frontiers everyone expects

Europe's tiny territories produce the short borders most people already know. The Gibraltar–Spain border runs east to west for 1.2 km across the isthmus, separating Gibraltar from the Spanish town of La Línea de la Concepción. Gibraltar was ceded to Great Britain under the Treaty of Utrecht in 1713, Spain built fortified lines just north of the isthmus in 1730, and the United Kingdom put up the fence that fixed the present line in 1909. Spain still disputes sovereignty over the isthmus, including the ground where Gibraltar International Airport stands. For decades it was a hard frontier with identity checks, and Franco closed it entirely in June 1969; it did not partly reopen until December 1982. According to the border's Wikipedia article, those checks were lifted on 15 July 2026, when Gibraltar began to be treated as part of the Schengen Area under an EU–UK arrangement.

Vatican City's border with Italy is about 3.2 km long and encloses less than half a square kilometre, a state only 1.05 km long and 0.85 km wide. The line was drawn by the Lateran Treaty of 1929, which ended the dispute between the popes and the Italian state that had begun when Rome was taken in 1870. Its planners followed the fortification walls built under Paul III, Pius IV and Urban VIII; where there was no wall, the line of certain buildings became the boundary, and for one short stretch a modern wall was built.

Monaco, the world's second-smallest state at 2.08 km², is surrounded on three sides by the French department of Alpes-Maritimes. Wikipedia's border list gives its frontier as 4.4 km, while Wikipedia's main article on Monaco gives 5.47 km, a reminder that short borders are hard to measure consistently when they run through streets and along the coast. The Franco-Monégasque Treaty of 1861 recognised Monaco's sovereignty; France remains responsible for its defence.

Passport Island and Hans Island: borders drawn across islands

The surprise entries on the list are borders that did not exist until recently. Saudi Arabia and Bahrain share no land at all, except on Passport Island, an artificial island built midway along the 25 km King Fahd Causeway, which opened on 26 November 1986. The island was designed as two halves joined by an isthmus, the western half Saudi and the eastern half Bahraini, with customs posts, two mosques and two 65 m tower restaurants. The line between them is about 196 m long, and it is the only border crossing between the two countries.

Hans Island is even newer as a border. This barren 130-hectare island in the Kennedy Channel of the Nares Strait, between Canada's Ellesmere Island and northern Greenland, was claimed by both Canada and Denmark for decades in a dispute nicknamed the Whisky War. On 14 June 2022 the two countries agreed to split it roughly in half, creating a land border of 1,280 m. It gave Canada its second land neighbour after the United States, and the Kingdom of Denmark its second after Germany.

Peñón de Vélez de la Gomera, Baarle and Kataja: the shortest single stretches

Several countries share borders made of many pieces, and some of those pieces are shorter than the Kazungula line. The shortest is at Peñón de Vélez de la Gomera, a rocky Spanish outpost on the Moroccan coast 119 km south-east of Ceuta. It was an island until 1930, when a violent thunderstorm washed enough sand into the channel to join it to the mainland. The resulting sandy isthmus forms a land border of 85 m according to the peninsula's article, or 75 m in Wikipedia's border list. Both sources rank it as the shortest single land-border segment in the world, with the list placing an 80 m segment between Romania and Ukraine, at K Island, just behind it. The 1.9-hectare rock is administered directly from Madrid and inhabited only by a small number of Spanish military personnel, and Morocco asserts a claim to it, as it does to Spain's other plazas de soberanía in North Africa.

Belgium and the Netherlands share 31 separate border segments, more than any other pair of countries, and several of the shortest run through the twin towns of Baarle-Hertog and Baarle-Nassau. Baarle-Hertog is made up of 26 parcels of land, many of them Belgian exclaves inside the Netherlands, the product of medieval land deals between the Lords of Breda and the Dukes of Brabant that the Treaty of Maastricht confirmed in 1843. Wikipedia's border list records segments there of 210 to 260 m.

In the Gulf of Bothnia, Sweden and Finland share the islet of Kataja. When the border was set in 1809 it ran between two islands, Swedish Kataja and Finnish Inakari. Post-glacial rebound has since lifted the land enough to join them, so a sea boundary became a land border of a few hundred metres, about 420 m in the island's own article and 320 m in the border list, marked by two cairns.

Russia–North Korea, Turkey–Azerbaijan and Afghanistan–China: short, but not the shortest

Several borders that people expect to top the list fall just outside it. Russia's land border with North Korea is only 17 km, running along the middle of the Tumen River, plus 22.1 km of maritime border. It is the shortest of all Russia's international borders, first fixed by the Convention of Peking in 1860 and set out in a treaty signed on 17 April 1985.

Turkey and Azerbaijan meet along the Aras River, where Turkey's Iğdır Province touches Azerbaijan's Nakhchivan exclave. The border's own article gives 17 km, while Wikipedia's border list gives 9 km and ranks it the seventh-shortest border between two countries. Either way it is the shortest border for both countries. Afghanistan and China share 92 km at the end of the Wakhan Corridor, following the watershed of the Mustagh Range over passes such as the Wakhjir. With Afghanistan on UTC+4:30 and China on a single national time of UTC+8, it marks the greatest time-zone jump across any land border. On the Caribbean island of Saint Martin, France and the Netherlands share a 16 km border that is completely open.

Ten short borders compared, from 155 metres to 92 kilometres

The first seven rows are the seven shortest complete borders between two countries in Wikipedia's "List of countries and territories by land borders". The last three are well-known short borders included for comparison, not a continuation of a strict ranking.

The two European microstates on the list are compared directly in is Monaco bigger than Vatican City?, and the history behind the fence at La Línea is told in what is Gibraltar?, the territory Spain ceded to Great Britain under the Treaty of Utrecht in 1713.