Rarely available classic six home with all external rooms. Off a semi private landing, enter into a lovely square gallery off of which the main rooms of this special home flow. The corner living room is gracious with both East and South tree-lined exposures, elegant built-ins and decorative fireplace. Next to the living room, the large formal dining room faces East onto tree-lined Madison Avenue as do the oversized eat-in kitchen with built/in banquet, a separate pantry, a closeted washer and dryer and spacious staff room with bathroom. The staff room is bright and cheery with its lovely street views, making it perfect as a third bedroom. The bedroom wing has 2 large bedrooms and 2 full bathrooms. The master suite has good closets, faces South onto tranquil 90th Street and has a new bathroom outfitted in statuary white marble and Waterworks fittings. The secondary bedroom has lovely built-ins and closets and is serviced by a restored hall bathroom, which works well as a powder room also. The entire apartment has wonderful prewar details, stunning original hardwood floors, high beamed ceilings and through the wall air conditioning. There is a great flow and beautiful light in every room. 21 East 90th Street is a full service white glove, prewar cooperative located in Carnegie Hill's Museum Mile perfectly situated a half block from Fifth Avenue and the Engineer's Gate entrance to Central Park and the Reservoir. Building amenities include a private storage bin, bike room, pets are welcome and pied a terres allowed.