If you're looking for a quick hike through wild Florida close to Jacksonville, there are actually plenty of options. Cradle Creek Preserve is one opportunity you might want to try. It's similar to Castaway Island Preserve on the other side of the Intracoastal, just smaller.
When we visited Cradle Creek Preserve in early April, we had the place mostly to ourselves on a perfect day. We met a couple who had parked their bicycles in the lot, as well as a man with a scope and binoculars who was watching an eagle's nest. He let our kids borrow his binoculars. That was nice, though I'm not sure the kids saw much.
I overheard the birdwatching guy tell the bike riding guy he might have left his iPhone on top of his car. I made a mental note to check it out when we got back to the lot, since I figured a birdwatcher might be there all day. And there it was, an iPhone hooked up to a lense adapter for the scope he was using.
It was a good teachable moment for the kids. I'd just bought my wife a new phone, but since money does not grow on trees like mistletoe here, we got a Moto something rather than an iPhone or Samsung. But I had told my kids how much an iPhone would have cost us. This man did not deserve to lose his phone to some dishonest passersby.
Of course we returned the iPhone, and we received plenty of thanks, including a chance to see some of the sweet photos this gentleman had taken in recent days of the eagle family. Yes, I said days. He might be there right now. In fact, if I meet him again, I'll ask if we can add some of the photos to this website.
If you end up at Cradle Creek, bring some binoculars and bug spray. It's a nice stroll through the woods. In the spring, you'll probably see hawks, osprey, and some eagles. Maybe a few people, too.