This PLSS map is from the Bureau of Land Management. Is depicts the PLSS for Walton County, Florida, which just happens to be where I live. The BLM website that this comes from has maps at the state and county level for the PLSS. In conjunction with this information, one can find out where National Parks are, what areas are under Department of Defense control, and so on.  http://geocommunicator.gov/LSIS6/map.jsp