Catherine the Great filmed at Rundale Palace, Bauska. This baroque palace in Latvia stands in for the Winter Palace, with its courtyard hosting a return from war and troop assemblies. On screen it's St Petersburg's Winter Palace.
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 Bauska and it tells you what was shot around you, how to get there, and whether you can actually go in.
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