Lake Okeechobee 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 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, the wetlands built up the layers of peat rapidly enough (reaching thick) to
U.S. Route 441 in Florida U.S. Route 441 in Florida U.S. Route 441 (US 441) in Florida is a north–south United States Highway. It runs from Miami in South Florida northwest to the Georgia border north of the Lake City area. Like all AASHTO designated highways in Florida, US 441 always carries a FDOT designated hidden state road number: Concurrences with U.S. routes include US 98 from Royal Palm Beach to Okeechobee, within the vicinity of Lake Okeechobee, US 192 between Holopaw and Kissimmee, US 17-92 from Kissimmee to Orlando, SR 44 from Mount Dora to Leesburg, US 27 from Leesburg to Ocala, US 301