North Korea vs South Korea
The division of the Korean peninsula began with the end of World War II and the division of that territory among the Allies, but it became final only in 1953, the year the Korean War ended - in fact, although not in fact. the papers because a peace treaty was never signed, only an armistice. That year, as part of the agreements that ended the armed conflict, a "demilitarized zone" was created four kilometers wide (two on each side of the 38th parallel) impossible to cross and which is, despite its name, the most militarized area on the planet.
Within that area there is a "joint security area", which is the only point where the soldiers of the two Koreas are face to face, and within that area there is, in turn, a "military demarcation line", always along the 38th parallel, which is the true border between the two Koreas. It is the only place in the world where a handful of South and North Koreans can see each other.
Kim Il-sung founded North Korea in 1948, and his family dynasty has ruled the country ever since, passing control from father to son. In the same period, in South Korea there were six republics, a revolution, two coups, and the transition to free and fair elections, in addition to 19 presidencies.
It may sound like an urban legend, but some research suggests that North Korean men are on average shorter than their southern neighbors. Professor Daniel Schwekendiek of Seoul's Sungkyunkwan University studied the heights of North Korean refugees as they crossed the border into South Korea and found an average difference of between 3 and 8 centimeters. Schwekendiek points out that the height difference cannot be attributed to genetics, as the two populations are the same in this regard.
In South Korea, the Seoul subway transports five and a half million passengers every day through one of the most extensive networks in the world, with 21 lines and more than 300 kilometers of tracks. Each section costs 1,350 South Korean won, just over $ 1.20, a price that includes access to one of the fastest wireless internet services on the planet in the most connected country on the globe (South Korea introduced 5G technology at Pyeongchang Olympic Games, the step prior to its international commercialization).
North Korea has the Pyongyang subway which only has two lines and was historically something of a state secret. Until 2010 foreigners could only visit two stations, then the permit was extended to six and only in 2015 the entire network was opened to visitors. Not only is it one of the deepest subways in the world (it was built in the 1970s at a depth of 100 meters with Soviet aid to act as a nuclear shelter) but it is also the cheapest: each trip costs five North Korean won, equivalent to one penny on the dollar.