Where was The Organist at St. Vitus' Cathedral filmed?

1929 film by Martin Frič

The Organist at St. Vitus' Cathedral (1929) was filmed in Prague Castle and Kavalírka mansion, 2 places named in its Wikipedia article, in the Czech Republic. Wikidata records no filming location for it at all, so the article is the only recorded source. Each place says where its claim comes from.

See them on the map → Wikipedia Source data