Conversation so far:
What property did William Randolph Hearst have in California?
Beginning in 1919, William Randolph Hearst began to build Hearst Castle, which he never completed, on a 240,000 acres ranch at San Simeon, California.
Did William Randolph Hearst live in Hearst Castle?
By 1925 William Randolph Hearst and his wife Millicent had effectively separated and he held court at Hearst Castle with his mistress, the actress Marion Davies.

Question: What was interesting about Hearst Castle?
Self-contained rewrite: What was interesting about Hearst Castle?