A fence in the demilitarized zone in Paju is decorated with ribbons calling for the unification of North and South Korea.Kim Hong-Ji/Reuters

The 25th anniversary of the fall of the Berlin Wall was on Sunday. The partition between West and East Germany lasted from 1961 to 1989. Much has changed since then. But there still quite a few walls that separate people across the world.

Here are some of them.

Israel’s Security Barrier

Finbarr O'Reilly/Reuters

In 2002, Israel started work on a 420-mile wall separating itself from the West Bank. It is mostly 5 meters of wire and mesh, but there are sections that are 8 meters tall and made of solid concrete, with watchtowers for snipers. The route of the wall does not follow Israel's pre-1967 borders, which the U.S. has said should be the basis of a possible peace deal that would result in a Palestinian state; the barrier leaves 6 to 8 percent of occupied Palestinian territory on the Israeli side.

To mark the fall of the Berlin Wall and draw attention to their plight, some young Palestinians dug a hole through the barrier.

U.S.-Mexico Border

Samantha Sais/Reuters

There are in fact three border fences used to separate the world’s richest country from its much poorer neighbor—built by Arizona, California, and Texas.

Work on border fences started in 2006, and the U.S. government has spent $3.4 billion on border fencing, with 640 of a planned 652 miles of fencing and vehicle barriers completed. Most strikingly, the Californian fence actually cuts across the beach and juts into the sea at Tijuana. There were also plans to put a series of towers with sensors across most of the 2,000-mile border, but the Obama administration ended funding for that effort in 2010.

Northern Ireland’s Peace Walls

Cathal McNaughton/Reuters

These walls—also known as peace lines—keep Catholic and Protestant neighborhoods separate, and despite the 1997 Good Friday Agreement that brought peace to Northern Ireland, they still stand. The first walls were built in 1969, early on in the 30-year period of conflict in Northern Ireland known as the Troubles. Sadly, there are actually more of them now. There are currently 48 peace walls across Northern Ireland, mainly in Belfast and Londonderry, up from just 18 in the 1990s. They stretch in total for more than 21 miles. The Northern Ireland Executive Committee, which governs Northern Ireland, is committed to the removal of all peace lines by 2023.

North Korea’s DMZ

Kim Hong-Ji/Reuters

The Koreas are still technically at war and the de facto border, ironically named the Demilitarized Zone, is the most heavily armed border in the world. It runs for 160 miles and is 2.5 miles wide. There is constant provocation and antagonism along the border: On Monday, South Korean troops fired warning shots at their northern counterparts who approached the border.

Spanish-Moroccan Fences

Juan Medina/Reuters

The fences separate Morocco and the towns of Melilla and Cueta, two small bits of Spanish territory in North Africa. In the 1990s, Spain built two 4-meter-high steel walls that each run for 7 kilometers to prevent illegal migrants from reaching Spanish soil, and therefore the European Union. It’s not working: Hundreds frequently rush the border to try to get in. Recently, Morocco joined the efforts to keep migrants from leaving and is installing a wall topped with razor wire along its side of the border.

More profoundly, the fences are a rare physical illustration of the enduring gulf between Europe and Africa, two continents separated by poverty, war, and a sea that tens of thousands are trying to cross in search of a better life.

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