KI introduced this stunning 109,000-square-foot house
in his blog
This is a view of the Biltmore house from the Esplanade which is probably about 1/4 mile from the house. How would you like to mow that lawn? The size of the living space in the house is about 4 acres and it is the largest private residence in the U.S. It was built by George Vanderbilt who inherited a vast fortune. His grandfather Cornelius amassed the unheard of $150 million in shipping and railroads. Cornelius' son doubled the fortune to $300 million which in today's money would be worth about 90 some odd billion if I heard the tape correctly. But they had no sinks in the 43 bathrooms even if they had the then new commodes.
See also Arnold Chase's Mega Mansion, Among USA's Largest Single Family Houses