Parasite filmed at Jahamun Tunnel stairs, Seoul. The staircase beside the tunnel that the family runs down in the flood sequence. On screen it's The stairs to the semi-basement.
Probable Named in published production coverage; the coordinate is the place itself, checked against a gazetteer.
Venture keeps every scene location on one map, sorted by how far you'd have to walk. Open it in Seoul and it tells you what was shot around you, how to get there, and whether you can actually go in.
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