A RARE MASTERPIECE ON SIESTA KEY- Opportunities like this come once in a lifetime. Penthouse #401 at Halcyon Siesta Key is more than a residence--it's a statement of luxury and exclusivity. Nestled in a boutique six-unit building, this is the first and only unit ever offered for sale, making it as rare as the quartz sands of Siesta Key Beach, just beyond your floor-to-ceiling windows. Step into your private foyer and take in breathtaking, uninterrupted Gulf views. This meticulously designed 3,525 sq. ft. residence blends modern sophistication with coastal elegance. At its heart, a chef's dream kitchen features top-of-the-line Wolf appliances, an oversized island, double ovens, two sinks, a walk-in pantry, built-in wine fridge, coffee bar, and custom cabinetry--perfect for entertaining and effortless daily living. The open-concept design seamlessly connects the kitchen, dining, and living spaces, enhanced by high-end finishes, poured terrazzo floors, and Lutron-controlled lighting and shades. Wake up to endless ocean views from the primary suite, a true sanctuary with a spa-inspired en-suite featuring heated floors, dual vanities, an oversized glass-enclosed shower, and a sculptural soaking tub. Step onto your private 674 sq. ft. wraparound balcony--ideal for morning espresso, sunset cocktails, or simply embracing Siesta Key's year-round coastal lifestyle. Three additional guest suites each offer en-suite baths and spacious closets. A full-size laundry room, ample storage, and a powder room for guests complete the thoughtful layout, with custom details throughout. A private 2-car garage adds convenience and security, a coveted feature in this exclusive Gulf-front retreat. Living at Halcyon Siesta Key is an elevated experience, with first-class amenities including on-site maintenance, a historic clubhouse, a gulf-front pool, grill area, fire pit, and private beach access. Siesta Key's finest dining, shopping, and vibrant Village are moments away, with easy access to both north and south bridges. More than a home, Penthouse #401 is a legacy--a rare opportunity to own one of the most distinguished Gulf-front addresses on Florida's most celebrated beach.