At MM 50 East Sister Rock Island is a ¼ mile off the Atlantic shore of Marathon. On the private island sits a dream come true getaway home with 5000+ square feet of living area including a 2700 square foot veranda, boat dock (fisherman's dream), helicopter launch pad and many more surprises. Built on a coral reef (a diver and snorkelers dream), and complete with every necessity except AC which not needed with the cooling trade winds during every season and over a dozen sliding glass doors. East Sister Rock Island is powered by natures energy. Wind and solar panels supply constant electricity to the island.