The Florida Keys extend from just south of the city of Miami (Soldier Key) to the Dry Tortugas, a distance of 150 miles. They are composed of two different types of calcium carbonate (i.e., limestone) rock. The upper Keys are exposed sections of former living coral reef (Pleistocene–Key Largo Limestone) and the lower Keys are lithified oolite (Pleistocene–Miami Oolite) accumulations. The Key Largo Limestone contains coral species similar to the modern-day reef. In places it is greater than 170 feet thick. I propose that the Key Largo Limestone coral reef tract developed during the period of slow Floodwater retreat spanning from 500 to over 1,000 years following the one-year-long global Flood of Genesis.