655 6Th Ave

The O'Neill is a landmarked seven-story, late-19th-century cast-iron and masonry building originally completed in 1887 and converted to condominiums in the 2000s. Its neo-Grec/Beaux-Arts heritage is evident in the gilded domes, high ceilings and preserved period detailing such as decorative moldings, antique doors and fireplaces. The property holds a small collection of sizable loft-style residences—primarily two- and four-bedroom plans—with dramatic ceiling heights (often 12–14 feet), broad windows, wide-plank hardwood floors and open-plan living areas that recall townhouse scale. Individual homes commonly include eat-in kitchens with high-end appliances, pantry or kitchen islands, generous walk-in closets and spa-like baths with soaking tubs and double vanities; many offer private outdoor space from Juliet balconies to larger terraces. Shared amenities reflect full-service urban living: a 24-hour attended lobby and concierge, on-site superintendent, deeded or common storage, and a professionally landscaped roof deck with outdoor kitchen and grilling/dining areas. The building is pet-friendly, provides generous storage options and sits on a Chelsea/Flatiron block with immediate access to grocery options, restaurants, parks, galleries and multiple transit lines, combining historic character with contemporary residential conveniences.