Far Off
The narrowest stretch of water between two countries is about 250 m, between Spain’s Perejil islet and the Moroccan coast. Singapore and Malaysia come next at roughly 600 m across the Strait of Johor, then Greece and Turkey at about 2 km.
The criterion matters. Countries that share a land border are zero distance apart: Vatican City touches Italy, Zambia touches Botswana. The ranking below covers pairs separated by water, smallest gap first. Record-setting land borders get their own section further down.
| Pair | Shortest gap | Where |
|---|---|---|
| Spain / Morocco | ~250 m | Perejil islet |
| Singapore / Malaysia | ~600 m | Strait of Johor |
| Greece / Turkey | ~2 km | Kastellorizo / Kaş |
| Australia / Papua New Guinea | 3 to 4 km | Saibai Island |
| Japan / Russia | 3.7 km | Cape Nosappu / Kaigara |
| Russia / United States | 3.8 km | Diomede Islands |
| Denmark / Sweden | 4 km | Øresund |
| Egypt / Saudi Arabia | ~6 km | Strait of Tiran |
| Trinidad and Tobago / Venezuela | ~11 km | Bocas del Dragón |
| United Kingdom / France | 33.2 km | Strait of Dover |
1. Spain and Morocco, 250 metres
Perejil is an uninhabited rock of less than half a square kilometre, administered by Spain, sitting roughly 250 m off the Moroccan shore. The same two countries also share two land borders, at Ceuta and Melilla, and face each other across the Strait of Gibraltar, 14 km wide at its narrowest.
Detail. Morocco claims Perejil and briefly occupied it in July 2002 before both sides returned to the status quo. So this is simultaneously the smallest measurable gap between two countries and the most disputed one: include the islet and the answer is 250 m, exclude it and the answer jumps to 14 km. The land borders are not in dispute, at 8 km around Ceuta and roughly 11 km around Melilla.
2. Singapore and Malaysia, 600 metres
The Strait of Johor, which separates Singapore from the Malay Peninsula, narrows to about 600 m. The road and rail causeway linking Woodlands to Johor Bahru is 1,056 m long.
Detail. This is almost certainly the most heavily crossed international water boundary on foot and by motorbike anywhere, with hundreds of thousands of daily movements in both directions. The causeway has been cut only once in dramatic fashion, in 1942, when retreating British troops blew a section of it.
3. Greece and Turkey, 2 kilometres
Kastellorizo, at the far south-eastern edge of the Aegean, lies just over 2 km from the Turkish town of Kaş. The ferry crossing takes about twenty minutes.
Detail. Kastellorizo sits roughly 125 km from the nearest other Greek island and 2 km from Turkey. That sixty-fold mismatch between physical proximity and political ownership underpins much of the Greek-Turkish argument over exclusive economic zones in the eastern Mediterranean.
4. Australia and Papua New Guinea, 3 to 4 kilometres
Saibai Island, in the Torres Strait, is Australian. The Papua New Guinean coast sits opposite, 3 to 4 km away depending on the source. The Torres Strait Island Regional Council gives 3 km, Wikipedia gives 4 km; the figure shifts with the measuring point along a heavily indented shoreline.
Detail. A 1978 treaty lets residents of designated coastal villages on both sides cross freely for traditional purposes, without passport or visa. It is one of the few international borders routinely crossed in a small aluminium boat, a fifteen to twenty minute run.
5. Japan and Russia, 3.7 kilometres
From Cape Nosappu, at the eastern tip of Hokkaido, Kaigara rock (Signalny in Russian), the first of the Habomai Islands, is 3.7 km away. On a clear day it is visible from shore.
Detail. These islands are administered by Russia and claimed by Japan since 1945. The dispute is unresolved and the two countries have never signed a peace treaty. Whether you are measuring an international boundary at all depends on which map you use.
6. Russia and the United States, 3.8 kilometres
The Diomede Islands, in the middle of the Bering Strait, are 3.8 km apart. Big Diomede is Russian and uninhabited; Little Diomede is American, with a village of about a hundred people.
Detail. The International Date Line runs between them. With the time zones actually in use, Big Diomede is 21 hours ahead of Little Diomede, 20 in summer. Cross 3.8 km and you skip most of a day. In winter the sea ice sometimes closes the gap entirely.
7. Denmark and Sweden, 4 kilometres
The Øresund narrows to 4 km between Helsingør in Denmark and Helsingborg in Sweden. Ferries shuttle across in about twenty minutes, all day.
Detail. The strait runs 118 km long and varies from 4 to 28 km wide. The two countries are also joined 45 km further south by the Øresund bridge-tunnel between Copenhagen and Malmö, which crosses a considerably wider stretch.
8. Egypt and Saudi Arabia, about 6 kilometres
The Strait of Tiran, at the mouth of the Gulf of Aqaba, leaves about 5 to 6 km between the Sinai Peninsula and Tiran Island. The Egyptian and Saudi shores of the gulf itself are roughly 13 km apart.
Detail. Tiran Island was administered by Egypt until a transfer agreement with Saudi Arabia ratified in 2017, which was challenged at length in Egyptian courts. Before that agreement, this pair would not have appeared in a ranking like this one.
9. Trinidad and Tobago and Venezuela, about 11 kilometres
The north-western tip of Trinidad faces the Paria Peninsula across the Bocas del Dragón. The shortest distance between Trinidad and the South American mainland is around 11 km. Venezuela’s Patos Island lies about 4 km off the mainland and 10 km from Trinidad’s Chacachacare.
Detail. This is the point where a Caribbean island very nearly touches South America. Trinidad was joined to the continent until the end of the last glaciation, which is why its wildlife is South American rather than Caribbean.
10. The United Kingdom and France, 33.2 kilometres
The Strait of Dover is 33.2 km wide between South Foreland, near Dover, and Cap Gris-Nez. That is the shortest distance between the two countries.
Detail. The gap is ten times wider than the Diomedes and carries vastly more traffic: it is the busiest shipping lane in the world. The Channel Tunnel is 50.5 km long precisely because it does not follow the shortest line across.
The shortest land borders
When two countries touch, the distance between them is zero and the ranking becomes a different question: how long is the border?
- Zambia and Botswana: roughly 150 m on the bank of the Zambezi at Kazungula, the shortest international boundary in the world, now spanned by a bridge.
- Italy and Vatican City: a 3.2 km perimeter. Vatican City is entirely enclaved within Rome.
- Spain and Morocco at Ceuta: 8 km.
- France and the Netherlands: 16 km on the island of Saint Martin, the only land border those two countries share.
- Canada and Denmark: the newest border on Earth, drawn across Hans Island in the Nares Strait in 2022.
Italy and San Marino are the other complete enclave case, with a border of roughly 37 to 39 km.
Three cases where the number depends on the map
Perejil, Kaigara and Tiran have one thing in common: the record hinges on who recognises what. Morocco claims Perejil. Kaigara is Russian on Russian maps and Japanese on Japanese ones. Tiran changed hands in 2017 under a contested agreement.
Any ranking of the closest countries is therefore conditional. It is the same reason to state the criterion before the number as with the most isolated cities in the world, where the order flips entirely depending on what you decide to measure.
What 3.8 kilometres actually gets you
On the Diomedes, physical distance has almost nothing to do with practical distance. No regular service connects the two islands. There is no border post. A resident of Little Diomede wanting to visit a place 3.8 km away must, legally, clear a Russian port of entry more than a thousand kilometres off.
That is the same gap between straight-line distance and real travel time found in the shortest flights in the world: a two-minute hop can take a full day to arrange.
The mirror piece: the most isolated cities in the world. Going further: the 10 shortest flights in the world, the longest straight line on Earth and what is on the other side of the Earth.
Frequently asked questions
Which two countries are the closest in the world?
If land borders count, several pairs are zero distance apart, including Italy and Vatican City, Italy and San Marino, and Zambia and Botswana. Counting only countries separated by water, the record belongs to Spain and Morocco, about 250 m apart at Perejil islet, ahead of Singapore and Malaysia at roughly 600 m across the narrowest part of the Strait of Johor.
How far apart are Russia and the United States?
3.8 km, between Big Diomede (Russia) and Little Diomede (United States), in the middle of the Bering Strait. The strait itself is about 82 km wide between the two continents, from Cape Dezhnev to Cape Prince of Wales. The two islands are split by both the maritime boundary and the International Date Line, producing a 21-hour time difference over less than four kilometres.
What is the shortest land border in the world?
The one between Zambia and Botswana, on the Zambezi at Kazungula: roughly 150 m, with sources giving 135 to 150 m. It joins two tripoints, one with Namibia and one with Zimbabwe, in a spot where four countries very nearly meet at a single point. A road and rail bridge has crossed it since 2021.
Can you see Morocco from Spain?
Yes. The Strait of Gibraltar is 14 km across at its narrowest, between Point Marroquí and Point Cires. On a clear day the Rif mountains are plainly visible from the Andalusian coast, and the lights of Tangier are visible at night. Ferries run from Tarifa to Tangier in 35 to 60 minutes depending on the vessel.
What is the world’s newest international border?
The Canada-Denmark border on Hans Island, in the Nares Strait. The agreement signed on 14 June 2022 ended a dispute of nearly fifty years by splitting the 1.2 km² island along a natural ravine, with roughly 60 per cent going to Denmark through Greenland and the remainder to Canada. It is the first land border those two countries have ever had.