This is a very nice Florida Preserve. There are man-made lakes created from mining. The water is crystal clear and you can see the bottom until it drops off. There are trails that go around the lakes and a trail that goes into the swamp where there are freshwater and saltwater marshes, and pine-covered sandhills.
There are two access points from which to start hiking. From Spring Hill either take US 19 to 595 and then to Burnt road, or keep going on 595 to 597 and go North to Burnt Road.
http://www.tripleblaze.com/trail.php?c=3&i=2529