The need to build large monuments bearing a strong symbolic value is common to every organised society.
The use of huge stones appears to be well adapted to building these monuments.
"Megalithic" monuments are therefore, not surprisingly, found all over the world, even though most were built at different periods in time (right up to the 19th century, in Madagascar), and are unrelated. However, they are the result of comparable needs leading to comparable responses. This well-known "convergence phenomenon" is common and especially in biology.
The Bugun-Ni dolmen in Korea. Like the other megaliths of the Far East, it has no cultural or chronological link with its equivalents in Western Europe.