Under contract-accepting backup offers. A rare opportunity to secure a true waterfront estate-sized homesite in the highly sought-after Palm Island enclave of Siesta Key. Located at the end of a quiet loop on Island Circle, this oversized 15,500 square foot pie-shaped double lot offers an exceptional 180+ feet of water frontage, creating a private, expansive setting rarely found this close to the beach. Surrounded by lush natural mangroves and multimillion-dollar residences, this property delivers the perfect balance of privacy, exclusivity, and direct boating access. A standout feature of the property is the grandfathered in 20x24 dock, significantly larger than what current regulations allow. Paired with a 14,000-pound boat lift and existing water and electric connections, for boating enthusiasts, this is not just a convenience, it's a major asset that cannot be replicated today. This homesite offers a strong foundation for new construction and the opportunity to design and build a custom waterfront estate tailored to your vision. The lot's unique shape and size allow for a larger footprint, creative architectural design, and maximization of water views. Palm Island is one of Siesta Key's best kept secrets, an intimate community of fewer than 140 homes known for its quiet streets, limited traffic, and strong sense of privacy and community. The property is ideally positioned across from a small community green space and just minutes from the world-renowned Siesta Key Beach, consistently ranked among the top beaches in the United States. Whether you are looking to build a full-time residence, a seasonal retreat, or a long-term investment property, this lot presents a rare combination of size, location, waterfront access, and redevelopment potential that is becoming increasingly difficult to find on Siesta Key. Opportunities like this are limited, especially with irreplaceable features like this dock and water frontage.