The Everglades is commonly described as a swamp, but it is more accurately a slow-moving river roughly 60 miles wide and only inches deep, flowing from Lake Okeechobee to Florida Bay. This 18,000-square-mile system is the only place on Earth where wild alligators and crocodiles share the same water, with about 200,000 alligators in the freshwater marshes and roughly 2,000 crocodiles along the saltwater coast.

The region has faced significant environmental pressures over the past century. Burmese pythons, introduced since the 1990s, now number between 100,000 and 300,000 and have sharply reduced populations of raccoons, opossums, and white-tailed deer. In July 2025, a state team removed 748 of the snakes, though the effort had little measurable impact on the overall population.

Lake Okeechobee, which covers 730 square miles, sits at the heart of the system. Despite its size, it averages only 9 feet deep. A dike built after a 1928 hurricane, which killed at least 2,500 people south of the lake, now separates the lake from the Everglades it once fed.

The region’s history includes an unusual economic boom in the 1890s, when snowy egret feathers sold for roughly twice the price of gold to supply the hat trade. Hunting reduced Florida’s wading bird population from about 2 million to half a million. A warden hired to protect the birds was killed in 1905, and the resulting national attention contributed to the Migratory Bird Treaty Act of 1918.

Long before European settlement, the Calusa people built a substantial society along the Everglades coast without farming. For about 2,000 years, they used canals and fish traps to harvest the estuaries, building towns on shell mounds and paddling dugout canoes as far as Cuba.

Several notable structures sit within or near the Everglades. In the 1960s, Aerojet General tested the AJ260, the most powerful solid-fuel rocket motor ever built, in silos near the national park. One motor was left in place after NASA chose liquid fuel, and it remains there today. A separate Nike Hercules missile base, armed with nuclear-capable missiles from 1964 to 1979, still stands and is now open for ranger tours.

The Florida panther population collapsed to roughly six animals around 1970. After the introduction of eight female Texas pumas in 1995 to address inbreeding, the population has recovered to between 120 and 230. Vehicle collisions are the leading cause of death for the remaining panthers.

The Everglades snail kite, a hawk that feeds almost exclusively on apple snails, adapted to the arrival of a larger invasive snail species by growing bodies and beaks roughly 10 percent larger within about a decade. The population has since climbed back toward 3,000.

The ghost orchid, a flower with no leaves and almost no visible stem, grows in the region’s strand swamps. Fewer than 2,000 exist in the United States, most in a single preserve, and a 1994 poaching plot became the subject of a book and film.

The Everglades sits on peat soil built up over 5,000 years. Since drainage began, the region has lost roughly 900 million tons of the soil, which oxidizes and burns away when exposed to air. South of Lake Okeechobee, farmland has sunk several feet as a result.

The system also supplies drinking water to more than 5 million people through the Biscayne Aquifer, a shallow limestone bed designated by the EPA as the sole source of water for Miami-Dade, Broward, Palm Beach, and Monroe counties.

Wading bird populations have declined sharply from historical levels. Nesting in the southern Everglades has fallen about 93 percent since the 1930s, from roughly 265,000 nesting birds to fewer than 20,000.

A single highway, the Tamiami Trail, opened in 1928 and unintentionally acted as a dam, blocking the southward flow of water. Removing sections of the roadbed has cost around $100 million and restored significant water flow, with the final stretch still under construction.

The Kissimmee River, straightened into a canal between 1962 and 1971, was partially restored starting in 1999. Crews backfilled 22 miles of the canal and reconnected 44 miles of the original river, and 159 bird species have returned to the area.

Everglades National Park, dedicated in 1947, was the first American park established to protect biodiversity rather than scenery. Fire is a natural and necessary part of the ecosystem, clearing woody growth and supporting ground-nesting birds. When the land is overdrained, however, dry-season fires can burn deep into the peat and destroy soil that took thousands of years to form.

The region’s ecosystem function depends heavily on periphyton, a mat of algae and microbes that forms the base of the food web and is highly sensitive to pollution. Sea level rise, about 9 inches over the past century, has pushed saltwater roughly 4 to 5 miles inland into freshwater marsh, and salt episodes can collapse the peat that holds the ground together.

The Comprehensive Everglades Restoration Plan, signed into law in 2000, is the largest ecological repair project ever attempted. It includes nearly 200 projects across 16 counties, with a cost estimated above $16 billion. The work remains incomplete, and parts of Miami-Dade were placed under water restrictions in February 2026 while restoration continued.

The name mostly associated with the region comes from writer Marjory Stoneman Douglas, who described it as a “river of grass” in 1947. The phrase captures what a century of drainage projects obscured: the Everglades was never a swamp to be conquered, but a slow, wide river that was nearly cut into pieces before it was widely understood as a living system.