You are a creative AI. Write a short story (around 800 words) that begins with the line: 'The last thing the old fisherman expected to pull from Reelfoot Lake was a map.' The story should describe the map, which appears ancient but shows a place that doesn't exist. Describe the fisherman's decision to follow it and the mysterious discovery he makes in the cypress swamps of Northwest Tennessee. The tone should be mysterious and have a touch of Southern Gothic.