Park Avenue keeps its rules quietly. The cornices line up, the limestone holds a common height, and almost every front door opens onto a cooperative with a board to satisfy. 900 Park Avenue broke all of that on purpose.
When Philip Birnbaum's tower rose at the corner of 79th Street in 1973, it became one of only two buildings to push past Park Avenue's uniform cornice line, a liberty the critic Paul Goldberger never forgave and one that still makes the building easy to pick out from blocks away. It went up where a 1917 mansion by John Mead Howells and I. N. Phelps Stokes had stood, and it arrived as something the avenue still has very little of: a condominium. On a corridor that is almost entirely co-op, that one fact has shaped who could buy here for fifty years.
Unit 25CD sits on the 25th floor, two original apartments combined into a single home of roughly 2,000 square feet, with two bedrooms and two and a half baths. About fifty feet of glass wraps the southern and eastern corner, so the rooms read from Central Park toward the downtown skyline and out across the low roofs of the East Side. Carol Kurth's interiors keep the attention there, with quiet materials and a library wall of built-ins that never competes with the view.
It returns now at 6,900,000, one of the few chances in a given year to own a condominium on the most cooperative of avenues. Down in the building's sunken, landscaped plaza, long considered the handsomest approach on Park, a Botero keeps watch.
