Okeechobee Mudfest, Florida, United States

History
Lake Okeechobee sits in a shallow geological trough that also underlies the Kissimmee River Valley and the Everglades. The trough is underlain by clay deposits that compacted more than the limestone and sand deposits did along both coasts of peninsular Florida. Until about 6,000 years ago, the trough was dry land. As the sea level rose, the water table in Florida also rose, and rainfall increased. From 6,000 to 4,000 years ago wetlands formed in much of what is now the lake, building up peat deposits. Eventually the water flow into the area created a lake, drowning the wetlands. Along what is now the southern edge of the lake, however, the wetlands built up the layers of peat rapidly enough (eventually reaching 13 feet (4.0 m) to 14 feet (4.3 m) thick) to form a dam, holding back the water in the lake until it rose high enough to the flow over the shore into the Everglades. At its capacity, the lake holds 1 trillion gallons (1,000,000,000,000) of water and is the headwaters of the Everglades.
The name Okeechobee comes from the Hitchiti words oki (water) and chubi (big), and means "big water". The oldest known name for the lake was Mayaimi (also meaning "big water"), reported by Hernando de Escalante Fontaneda in the 16th century. Slightly later in the 16th century René Goulaine de Laudonnière reported hearing about a large freshwater lake in southern Florida called Serrope. By the 18th century the largely mythical lake was known to British mapmakers and chroniclers by the Spanish name Laguna de Espiritu Santo. In the early 19th century it was known as Mayacco Lake or Lake Mayaca after the Mayaca people, originally from the upper reaches of the St. Johns River, who moved near the lake in the early 18th century. The modern Port Mayaca on the east side of the lake preserves that name. The lake was also called Lake Macaco in the early 19th century.