For the past year, we have been reminded how a hot border can turn into a full-scale war. Russia’s invasion of Ukraine is the most serious armed conflict in Europe since World War II. 

Theirs is not the only problematic border in Europe though. The world is full of tinderboxes, and the hope is none of these disputes escalates into a nuclear exchange.

To find demilitarized zones, buffer zones, contested border lines, and other areas on the brink of war, 24/7 Wall St. reviewed several sources, including U.N. resolutions and peacemaking, armistice, and ceasefire agreements. Zones are ordered loosely based on where they were established, except some zones were the subject of several agreements over the years. The parties that are on either side of these zones are not currently in open armed conflict, but skirmishes in many of these areas are not rare either. The Antarctic Treaty and Outer Space Treaty are somewhat different as they are international agreements regarding an area.

There are two contested zones in Europe that involve Greece and Turkiye – a disagreement over the militarization of islands in the eastern Aegean Sea, and the ongoing conflict on Cyprus between ethnic Greeks and Turks. (Greece and Turkey, however, are not among the 29 countries currently at war.)

Since Israel captured the Golan Heights from Syria and the Sinai Peninsula from Egypt in the Six-Day War in 1967, these borders have been hot spots at times. (Israel is also among the 13 countries with required military service for men and women.)

India has been at loggerheads with Pakistan over the Kashmir region since both nations gained independence in 1947. Those two countries fought a war over the area in 1971 and it remains a bone of contention today. India also shares a long border with China. It fought a war with China in 1962 that resulted in the loss of territory. All of those conflicts involving India run the risk of a nuclear exchange.

Speaking of China, the world’s most populous nation continues to rattle sabers over its claim to Taiwan, a situation that might draw in the U.S. 

And then there is the hottest spot of all, the border between North and South Korea, roughly along the 38th Parallel. A ceasefire halted the war in 1953, but did not formally end it.

Click here to see the national borders on the brink of war.