From Homes of the Rich:
Although we have HOTR in one of the feedreaders the picture above came from Clusterstock.
Location: 2 Margo Way, Alpine, NJ
Square Footage: 34,000
Bedrooms & Bathrooms: 8 bedrooms & 13 bathrooms
Sales Price: $20,000,000
This 34,000 square foot mega mansion located in Alpine, NJ sold for $20 million on December 29th, making it one of the most expensive homes ever sold in the state. Located at 2 Margo Way, the 27-room home first came on the market back in June of 2011 with an asking price of $34 million. It was then lowered to $29 million in March of 2012....MORE
Here's Biltmore House, kind of a Chambord feel with the spiral (but not double helical) staircase but smaller than the Château at 178,926 square feet: