A country’s border demarcates it from neighbouring countries and keeps it safe.
However, some borders are war zones where many people have died.
Here are 10 countries with the most dangerous borders.
South Korea/North Korea
The 160-mile border between North and South Korea is known as the Korean Demilitarised Zone (DMZ).
It is guarded by troops, barbed wire, and live landmines.
Hundreds of people have died in the more than 60-year-old conflict.
The DMZ was established as a buffer zone to keep the two countries safe from one another; anyone who crosses the boundary will be shot.
India/Pakistan
The India-Pakistan border is a 1,800-mile tightly guarded, deadly zone that is the only border visible from space due to high-voltage flood lights.
Since 1947, over fifty thousand people have been killed in three wars.
Israel/Syria
Israel and Syria have been at odds since Britain drew a border between them in the 1920s.
Both countries have fought each other several times over different territories.
Since the start of the Syrian Civil War, the border has seen a rise in violence and is now a live war zone.
Mexico/US
Since 1998, 8,000 undocumented migrants have died trying to cross the Mexico-US border, often crossing desert areas and rocky terrain.
The 1,989-mile border has the highest number of annual crossings globally. 500,000 illegal migrants cross the border illegally, with several hundred dying annually.
The El Paso-Juarez region is dangerous.
It is known for narcotics trafficking and violent encounters between police and gang groups.
Yemen/Saudi Arabia
The 1,100-mile border between Yemen and Saudi Arabia has been a place of violence and death for 65 years.
Saudi Arabia is faced with increased smuggled weapons, Al Qaeda terrorists, and economic refugees. This made them want to build a wall, but Yemen says it's against their shepherd-grazing rights.
In one day, 15 missiles and 130 mortars were launched into Saudi Arabia. The war has lasted since March 2015, with 6,000 civilians and soldiers killed.
In all these countries, land disputes, wars, and illegal crossings make their borders dangerous.