Game of Thrones filmed at Castillo de Zafra, Guadalajara. The isolated keep where Ned Stark's flashback duel is fought. On screen it's The Tower of Joy, Dorne.
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 Guadalajara and it tells you what was shot around you, how to get there, and whether you can actually go in.
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