Oheka Castle, the 127-room Long Island estate that inspired 'The Great Gatsby,' is heading to auction. Look inside.

Oheka Castle, described as the second-largest private home in the United States, is set to go up for auction on October 27 through Concierge and Adam Modlin of The Modlin Group. The 127-room Long Island estate is said to have inspired the parties depicted in F. Scott Fitzgerald's The Great Gatsby and has been used in film and television. Its original owner was financier Otto Hermann Kahn, who built the estate and named it after himself. The property has also served as a wedding venue for celebrities including Kevin Jonas and Megyn Kelly.

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