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Mansion has five stories -- mostly underground

The home sits on top of a hill over 8 acres in Rolling Hills, Calif. Read more about the underground mansion on the Yahoo! Homes’ Spaces blog.

Six-story mansion is five stories underground

Hacienda de la Plaz, located in Rolling Hills, Calif., goes five stories underground and includes an underground ballroom, Turkish bath-style spa room, a swimming pool, tennis courts, nine bedrooms and 25 bathrooms. The one-of-a-kind home was recently placed on the market. Read more about the underground mansion on the Yahoo! Homes’ Spaces blog.