Here's a
link to the Sarasota County parks system... a great map to illustrate the abundance of locations! Many of them have dirt trails. I imagine if you google ones that peak your interest you'll find more detailed information.
Another hidden gem is
Myakka State Forest, off of River Road heading into Englewood. It ONLY has dirt trails, and plenty of them. Beautiful scrub pine forest. TAKE WATER. There are no facilities and you will be in full sun for 98% of your run.
Also, don't forget to check out the area's
state parks.
Oscar Scherer would fit the bill, certainly.
And, of course... there's the beaches!
