There are only a select few offerings along Florida's Gulf Coast that can truly be described as irreplaceable. This extraordinary bayfront estate on Sanibel Island stands firmly among them. Set on approximately 1.6 acres, this is one of the largest buildable bayfront parcels on Sanibel Island, distinguished not only by its scale, but by its exceptional east-end location near the Historic Sanibel Lighthouse. Tucked away at the end of private Buttonwood Lane, the property enjoys a rare sense of seclusion while remaining just a short stroll to Sanibel's world-renowned white-sand beaches and moments from convenient on-and-off island access. The estate boasts approximately 150 feet of direct bay frontage, where gentle shoreline sands meet the shimmering waters of San Carlos Bay. A brand-new private dock extends gracefully into the bay, offering immediate boating access and an ever-changing panorama of sunrises, passing vessels, and coastal wildlife, also an ideal gateway for boating, paddleboarding, or sunset cruises. Beyond its natural beauty, the property's true distinction lies in its extraordinary development potential. According to the City of Sanibel Planning Department (Development Permit 88-7456), the parcel is allocated three dwelling units within the D2 - Upland Wetlands ecological zone, with a minimum lot size of 15,000 square feet. The generous acreage allows for subdivision into three single-family parcels, presenting a spectrum of possibilities from a legacy bayfront compound, to an intimate enclave of luxury residences, or a singular estate of remarkable scale and presence. Opportunities of this caliber, where size, zoning flexibility, waterfront access, and historic location converge, are exceedingly rare. Properties like this have not been available for decades, and it is unlikely one will present itself again. This is more than a parcel of land; it is a once-in-a-generation opportunity to reimagine and create something truly exceptional along the bay on Sanibel Island.