History and Geography of the Florida Keys

A Unique Archipelago with a Storied Past

Aerial view of Florida Keys
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The Florida Keys are a series of islands extending from the southeastern tip of Florida. They begin about 15 miles (24 km) 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 Native American tribes: the Calusa and Tequesta. Juan Ponce de Leon, who arrived in Florida in about 1513, was one of the first Europeans to find and explore the islands. His attempts to colonize the region for Spain was soundly defeated by the Native people.

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 associated with 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 to ever hit the United States. On September 2nd of that year, the hurricane winds of over 200 miles per hour (320 km/hr) hit the islands and a storm surge of over 17.5 feet (5.3 m) quickly flooded them. The hurricane killed over 500 people and the Overseas Railway (constructed in the 1910's 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 also still 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 sq km) 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 but 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. However, because of the islands' location between the Atlantic Ocean and the Gulf of Mexico, they are very prone to hurricanes. Because the islands have low elevations, are surrounded by water, and flooding from the storm's surges can easily affect large areas of the Keys, hurricanes can be especially problematic.

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 also 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 km) 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.