Welcome to Residence 3AD at 4 West 21st Street. A rare, full-floor–scale Flatiron District home offering privacy, flexibility, and long-term versatility. Spanning approximately 3,000 square feet, this thoughtfully combined residence delivers the scale and comfort of a private home with the freedom of condop ownership. With 10-foot ceilings, two separate entryways, and a layout designed to evolve over time, Residence 3AD is equally well-suited for families, co-purchasers, or long-term investors seeking adaptability. A gracious foyer opens to expansive, north-facing living and dining spaces that anchor the home, ideal for daily living, entertaining, or shared use without compromise. The kitchen is connected via a passthrough, maintaining separation while allowing ease of flow, and is complemented by a dedicated dining room and breakfast nook that support everything from weekday mornings to formal gatherings. The south-facing bedroom wing offers four generously proportioned bedrooms, providing exceptional quiet and privacy rarely found in this part of Manhattan. The primary suite functions as a true retreat, complete with a walk-in closet, en-suite bath, and an adjacent office or library, perfect for work-from-home flexibility or future reconfiguration. Designed by acclaimed architect Hugh Hardy, 4 West 21st Street is a boutique, full-service condop that offers the advantages of condo ownership. The building allows pets, unlimited subletting, pied-a`-terres, co-purchasing, gifting, and parents buying for children, making it an ideal choice for multigenerational living, friends buying together through an LLC, or investors seeking maximum flexibility. Amenities include a 24-hour doorman, landscaped common terrace, fitness center, and on-site parking. Located just steps from Madison Square Park, and surrounded by the best of Flatiron, NoMad, and Union Square, residents enjoy immediate access to top dining, culture, and green space, including Eataly, ABC Kitchen, Trader Joe's and more! Private showings available by appointment with The 212Bravo Team at Nest Seekers.