19 Gramercy Park South.

19 Gramercy Park South has just come on the market for $18 million, and Leslie Mason, townhouse specialist at Douglas Elliman, has been appointed the exclusive broker. Owned by designer Richard Tyler and his wife, Lisa Trafficante, this 37-room, 18,000 square-foot mansion is located on the southeast corner of 20th Street and Irving Place, directly overlooking Gramercy Park.

According to Mason, "19 Gramercy Park South is one of the finest houses remaining in private hands today. The owners have restored and maintained the house beautifully." The home was designed for gracious entertaining by Stanford White for Mrs. Stuyvesant Fish in the 1880's. Subsequently, it was purchased by Benjamin Sonnenberg to house his extensive art and furniture collection.

The corner property boasts a magnificent staircase; William & Mary drawing room; library; several sitting rooms, studios and reception rooms; two kitchens; six bedroom suites; and 13 fireplaces. It is topped with a penthouse ballroom with dramatic park views. Other extraordinary features include museum quality paneling and exceptional mantles, moldings and hardware throughout. In addition, the house is centrally air-conditioned.

"Gramercy Park has always been a choice area, and to have a house directly on New York's only private park also adds to the property's value and appeal," Mason said. "People always stop to admire the house. Whoever purchases this home will be investing in a part of New York history."