We visited the headsprings part of Rainbow Springs State Park in Dunnellon, Florida.

Their map:

The main part of the park is physically separated from the campground:

A sign with info about the history:

Pond and waterfall:

Natural Landmark since 1972:

Paths and the spring:

Caution, gators:

Info sign:

Selfie:

Swimming area:

Swimming area from other side:

Bumpy path:

Marshy area:

Bubbling sand GIF:

Waterfall GIF:

Waterfall long exposure:

A nice park. Apparently crazy busy in summer, but not so much in winter.