UN Buffer Zone, Cyprus
This demilitarized zone (known colloquially as the green line) was first established in 1964, and reached its current length in 1974 following the Turkish invasion of Cyprus. Much like the Berlin Wall of old, the barrier (which is made up of barbed-wire fencing, concrete wall segments, watchtowers, anti-tank ditches, and minefields) separates the island, and armed UN peacekeeping forces ensure there are no unauthorized crossings.