The largest homes on the market range from $5.9 million to $68.8 million, and the house with the smallest footprint on this list is 33,500 square feet.
Habitations on such a grand scale bring with them famous occupants, prominent families, renowned architects and imported special features with historic pasts.
Oh, and one of these mansions has a 5,000-square-foot closet.
"Homes of this scale are always fun to watch as they tend to require a very unique buyer," said Alison Schwartz, vice president of corporate communications for Move Inc., operator of Realtor.com. "We're looking forward to seeing who scoops these up, especially as we approach the high season for residential real estate."
In the following slides, find the largest for-sale properties currently listed on Realtor.com.
—By Colleen Kane, special to CNBC.com
Posted 24 March 2014