Spacious Home in prominent Key Colony Beach, neighborhood of Marathon and Coco Plum Beaches. Four bedrooms each with complete bath. Huge living spaces downstairs and upstairs neglecting the swimming pool and Crystal clear canal. Walking range from the Sunset Park. This might be your trip, financial investment, rental or your main house. House embellished by Chris E. Key West Designer. Secret Colony Beach is reached over the Sadowski Causeway, which connects Key Colony Beach to Marathon, Florida on the east side of the city. It lies straight south of the City of Marathon, covering a slim cut.Along.