The Three Musketeers filmed at Seegrotte, Hinterbrühl. The villain's boat trip to the Parisian dungeons was shot on a real underground lake, flooded when a mine was blasted. On screen it's Parisian dungeons.
Probable Named in published production coverage; the coordinate is the place itself, checked against a gazetteer. This is an area, not a spot. The coordinate is its middle, so use it to navigate to the place and not to line up a shot.
Planning the trip? The Austria travel atlas covers money, language and getting around
Venture keeps every scene location on one map, sorted by how far you'd have to walk. Open it in Hinterbrühl and it tells you what was shot around you, how to get there, and whether you can actually go in.
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