Lake Okeechobee is located in south Florida and is bounded by the Kissimmee River Basin to the north and Everglades National Park to the south. Lake Okeechobee is the largest lake (1,890 square kilometers [km2]) in Florida and encompasses a drainage area of over 14,200 km2. The lake provides agricultural water supply, back-up water supply for urban areas, flood protection to adjacent communities, critical bird and fisheries habitats, is part of the Okeechobee Waterway navigation canal, and offers boating-related recreation. Over the past 100 years, land use change and population increases have adversely impacted the health of the lake, mostly by extreme water level fluctuations and excessive nutrient loading mainly from agricultural activities. High-resolution bathymetric mapping was conducted in 2001 in Lake Okeechobee by the USGS, in cooperation with the South Florida Water Management District (SFWMD). High-resolution, acoustic bathymetric surveying is a proven method to map sea and lake floor elevations. Survey tracklines were spaced 1000 meters apart and orientated in a north-south direction. Tracklines collected in an east-west orientation (intersecting tracklines) functioned to serve as a cross-check and to assess the relative vertical accuracy of the survey. Ideally, vertical data values at the crossing should be exactly the same. In reality, this is not always the case due to random errors associated with the survey system. Several perimeter survey lines were also collected. Soundings were collected along each trackline at 3-meter spacing. Approximately 1,550 kilometers of survey lines were collected. In shallow areas, data were collected in a minimum of 0.6 meters water depth, unless potential damage to the bottom environment or the boat/motors was a significant possibility. This report serves as an archive of processed single-beam bathymetry data that were collected in Lake Okeechobee, Florida, in 2001. Geographic information System (GIS) data products include XYZ data, bathymetric contours, and USGS quadrangle maps and associated formal Federal Geographic Data Committee (FGDC) metadata.