It had semi-hidden rooms, multiple floors, and a basement that I was only in once. The latter was more full-height cellar than a basement, and revealed the layers of renovations from its long-ago origin as a tavern (rumor has it that Jesse James frequented). Sadly, while it was one of the oldest homes in a tiny town in Missouri, upon her death, the historical society could not afford to purchase it (even at really depressed prices), and my uncle, who was the executor of her estate, was not exactly appreciative of that possibility. So, while I'm told it still stands, it has been renovated to an almost unrecognizable state.
At any rate, that house was so unique that I can still remember almost every major detail from room to room, and I used to dream about it as having almost an entire hidden "house within a house," so fascinating it was to a young kid. But it did likewise scare me, with those semi-secret passages. 
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