The Hidden Lake Project is 585 acres of land in the growing West Pasco area, completely surrounded by residential development. Owned by the Southwest Florida Water Management District, it is not generally suitable for public access or recreation, and is largely unexplored, because it is mostly a swamp. In the midst of the reserve is Hidden Lake with an area visible from the air of probably 50 to 60 acres - making it one of the largest and most recognizable lakes in the area. It is impossible to miss this landmark when viewing a Google Earth image of West Pasco County.
As far as I can tell, there are two public access points to the Hidden Lake Project. One is at the dead end of Doe Court, where SWFWMD property fronts on the public right of way. And the other is from Ridge Road where a strip of land owned by Pasco Country, with a SWFWMD easement, runs north to the Project. The easiest access for proximity to Hidden Lake is the Doe Court gateway. There is a gate at this location allowing access to the preserve. Please climb over the gate on the hinged side.
If you succeed in finding this cache, or at least make it into the interior portions of the Hidden Lake Project, you will quickly realize why this is called "Hidden Lake". It is actually what is referred to as a "swamp lake" - which means that it is really a large swamp where the water in the center is so deep that no trees will grow. So the area seen as a lake from aerial views is only a small portion of the total land area covered with water. I am curious as to whether during an extended drought one could actually hike to the visible lake margin without wading through water.

Incredibly, the landscape eventually opens up into small clearings.

But as you continue to head toward Hidden Lake, the swamp returns. This is pretty much the end of the line - at least from this direction.
Congratulations to Flyingbird for a very challenging FTF.