The massive Juche Tower was a birthday present from North Korea to its original Great Leader.
"Juche" was the ideology Comrade Kim Il-sung structured his empire around, which roughly translates to "self-reliance." In loosest terms, it drew upon Marxist-Leninist principles and asserted that every Korean should harness their own destiny in order to make the nation great. There's much more to Juche; it has been credited with creating the cult of personality surrounding North Korean leaders. It would later become known by another name: "Kimilsung-ism."
The Juche Tower was built in 1982 on the banks of the Taedong River in celebration of Kim Il-sung's 70th birthday. As everything in North Korea is symbolic, the Juche Tower makes no exception. It's comprised of 25,550 blocks—one for every day of Il-sung's life. Some have even said that he was the architect of the grand monument to his own philosophy, but this is unlikely.
The monolithic structure is reminiscent of the United States' Washington Monument, and in fact Juche Tower is considered to be in direct competition with the famed Washington, D.C. monument, as it is exactly one meter taller than the American obelisk. This makes it one of the highest monuments in the entire world, second only to Houston's San Jacinto Monument.
The tower is a popular tourist destination, where visitors can ride to the top in an elevator to view Pyongyang from above. For the heights-avoidant, there are videos displayed at the base of the tower explaining the monument's significance to the Democratic People's Republic of Korea, to the philosophy of Juche, and to Eternal Leader Kim Il-sung.