Thornton Key Island Development Opportunity. Thornton Key near Stump Pass is a true bridgeless barrier island on Florida’s Gulf Coast, with a rare 8-lot, 3.41-acre waterfront assemblage that includes five buildable lots and offers multiple paths for value creation, including waterfront development, a limited private enclave, shared-ownership retreat, or strategic long-term hold. The assemblage supports the vision of multiple custom residences, private dock planning, boat lifts, and a low-density island concept positioned around boating, privacy, and Gulf Coast waterfront lifestyle. BBI zoning now permits noncommercial docks as a principal use, adding meaningful waterfront utility for development planning and future owner use. With direct boating access to the Intracoastal Waterway, Lemon Bay, Stump Pass, Boca Grande Pass, and the Gulf, the property is well positioned for buyers seeking a rare island opportunity with strong boating appeal. Located directly across the channel from Rum Bay Restaurant and close to mainland marinas, dining, parking, and slip options, Thornton Key combines island seclusion with practical access to mainland services. Arrival is by boat only, preserving the quiet, low-density character of the Bridgeless Barrier Islands. Gulf sunset views, natural island surroundings, world-class fishing access, and flexibility for personal use, shared ownership, boutique resale, or a unique rental concept when not personally occupied create a development opportunity in a great Gulf Coast vacation area. Seller financing is available for qualified buyers with a meaningful down payment.