from Pinellas:

Take US 19 to the Dunedin/ Oldsmar/ SR580 exit (north end of Countryside Mall)

   (or take McMullen Booth (Pinellas 611) to SR580 (at the 2800 block -- just before Countryside High School)

Head East on SR 580 for about 2.8 miles to the light at Philippe Parkway/ Safety Harbor/ SR 590 (the first traffic light east of McMullen-Booth -- just before the bridge over an arm of upper Tampa Bay)

From Hillsborough:

Alternative A: 

take I275 or the Causeway to US19 or McMullen-Booth/Bayside Bridge, head north, then follow the Pinellas directions.

Alternative B: 

Take Hillsborough Avenue West to Oldsmar (just over the Pinellas County line).

In Oldsmar (about a mile past the flea market), bear left at the light at SR 580

Go 2.3 miles  to the light at Philippe Parkway/ Safety Harbor/ SR 590 (traffic light just past the bridge over an arm of upper Tampa Bay)

From Philippe Parkway & SR580:

Go 1.3 miles south on Philippe Parkway to the park entrance (just before the stop light at Enterprise)

Turn Left into the park, then turn right at the stop sign (at the water) onto the main park road

from the main road, take the second left into the big parking lot by the big shelter by the Indian Mound