Been coming here since I was a kid and so have the manatees every winter. When the water temps in the St.Johns river drop below 72°F the manatees seek shelter in constant temp of the spring run. Not a ton of hiking available here but a decent 3.5 mile one way trail through Florida scrub and oak hammock. The rare and endangered Florida Scrub Jay can be found here. Directly adjacent to the park is a beautiful and at times challenging (for flat Florida) bike trail. Also adjacent to the park is an active train track, trains which can be heard fairly well from the campground. This was not a negative for us as the noise is not that frequent and and short duration. We also love trains, and they're a part of the areas history. One of the best campgrounds in a state park for separation from neighboring sites. Other than the trains it's been one of the quietest campgrounds we've experienced. The St.Johns River is great for paddling but can be thick with motorboats on the weekends. Blue Spring was privately owned as recently as the early '70's when it was aquired by the state and is a testament to the benefits of sound management and preservation.