Humanities › Geography History and Geography of the Florida Keys A Unique Archipelago with a Storied Past Share Flipboard Email Print JupiterImages/ Stockbyte/ Getty Images Geography Country Information Basics Physical Geography Political Geography Population Key Figures & Milestones Maps Urban Geography By Amanda Briney Geography Expert M.A., Geography, California State University - East Bay B.A., English and Geography, California State University - Sacramento Amanda Briney, M.A., is a professional geographer. She holds a Certificate of Advanced Study in Geographic Information Systems (GIS) from California State University. our editorial process Amanda Briney Updated September 16, 2019 The Florida Keys are a series of islands extending from the southeastern tip of Florida. They begin about 15 miles (24 kilometers) south of Miami and extend out toward the southwest and then west toward the Gulf of Mexico and the uninhabited Dry Tortugas islands. Most of the islands making up the Florida Keys are within the Florida Straits, a body of water located between the Gulf of Mexico and the Atlantic Ocean. The most populated city in the Florida Keys is Key West; many other areas are sparsely populated. Early Days of the Florida Keys The first inhabitants of the Florida Keys were Indigenous peoples: the Calusa and Tequesta. Juan Ponce de León, who arrived in Florida in about 1513, was one of the first Europeans to find and explore the islands. The Native people soundly defeated his attempts to colonize the region for Spain. Over time, Key West began to grow into Florida's largest town due to its proximity to Cuba and the Bahamas and a trade route to New Orleans. In their early days, Key West and the Florida Keys were a major part of the area's wrecking industry—an "industry" that took or "salvaged" valuables from shipwrecks. This activity was dependent on the frequent shipwrecks in the area. In 1822, the Keys (along with the rest of Florida) became an official part of the United States. By the early 1900s, however, Key West's prosperity began to decline as better navigational techniques reduced area shipwrecks. In 1935 the Florida Keys were struck by one of the worst hurricanes ever to hit the United States. On September 2, 1935, hurricane winds of over 200 miles per hour (320 kilometers/hour) hit the islands and a storm surge of over 17.5 feet (5.3 meters) quickly flooded them. The hurricane killed over 500 people, and the Overseas Railway (constructed in the 1910s to connect the islands) was damaged and service stopped. A highway, called the Overseas Highway, later replaced the railway as the main form of transportation in the area. The Conch Republic Throughout much of their modern history, the Florida Keys have been a convenient area for drug smugglers and illegal immigration. As a result, the U.S. Border Patrol began a series of roadblocks on the bridge from the Keys to the mainland to search cars returning to Florida's mainland in 1982. This roadblock later began to hurt the economy of the Florida Keys as it delayed tourists going to and from the islands. Because of the resultant economic struggles, the mayor of Key West, Dennis Wardlow, declared the city as independent and renamed it the Conch Republic on April 23, 1982. The city's secession lasted only a short time however, and Wardlow eventually surrendered. Key West remains a part of the U.S. Islands of the Keys Today the total land area of the Florida Keys is 137.3 square miles (356 square kilometers), and in total there are over 1700 islands in the archipelago. However, very few of these are populated, and most are very small. Only 43 of the islands are connected via bridges. In total there are 42 bridges connecting the islands; the Seven Mile Bridge is the longest. Because there are so many islands within the Florida Keys, they are often divided into several different groups. These groups are the Upper Keys, the Middle Keys, the Lower Keys, and the Outlying Islands. The Upper Keys are those located the farthest north and closest to Florida's mainland, and the groups extend out from there. The city of Key West is located in the Lower Keys. The Outer Keys consist of islands that are accessible only by boat. Hurricanes and Flooding The climate of the Florida Keys is tropical, as is the southern part of the state of Florida. Because of the islands' location between the Atlantic Ocean and the Gulf of Mexico, they are very prone to hurricanes. The islands have low elevations; the flooding from the storm surges that usually accompany hurricanes can, therefore, easily damage large areas of the Keys. Evacuation orders are regularly put into place due to flood threats. Coral Reefs and Biodiversity Geologically, the Florida Keys are made up of the main exposed parts of coral reefs. Some of the islands have been exposed for so long that sand has built up around them, creating barrier islands, while other smaller islands remain as coral atolls. Additionally, there is still a large coral reef offshore of the Florida Keys in the Florida Straits. This reef is called the Florida Reef, and it is the third-largest barrier reef in the world. The Florida Keys are a highly biodiverse area because of the presence of coral reefs as well as undeveloped forested areas. Dry Tortugas National Park is located about 70 miles (110 kilometers) from Key West and, since those islands are uninhabited, they are some of the most well preserved and protected areas in the world. The waters around the islands are home to the Florida Keys National Marine Sanctuary. Because of its biodiversity, ecotourism is becoming a large part of the Florida Keys economy. Other forms of tourism and fishing are the major industries of the islands.