Off-market? Maybe. Unreportable? Absolutely not. This 25-foot-wide Upper East Side townhouse is pure architectural drama—with colonial bones and a century of very cool secrets.

With its handcrafted Italian limestone facade and classical detailing, this New York townhouse offers plenty of curb appeal, along with a coveted address between Madison Avenue and Park Avenue.

The New York townhouse is the former home of legendary philanthropist David Rockefeller, who lived at the 40-foot wide Colonial Revival mansion with his wife for 70 years.