Basically, any area in Lake County that is SOUTH of Astatula or Howey in the Hills is in the South Lake Hospital District, and the area North is in the North Lake County Hospital District.
The link to the Lake County maps of the North & South Lake County Hospital Districts is HERE:
http://www.lakecountyfl.gov/pdfs/gis/maps/HospitalDistricts_22x34.pdf
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