Tom....this area is Three Sisters. Their website is
Three Sisters Springs Boardwalk Tour Crystal River Florida
It is right off 19, on the corner of 19 and Kings Bay Drive, less than a mile south of where 44 meets 19...can't miss it. The normal cost is $6.00...."Seniors" over 55 cost $5.00. Kids 10 and under are $4.00.
They drive you over there to the boardwalk, and you can stay there as long as you like. The bus ride is less than a mile. They then return you to the home base where you paid and parked your car. They say that the shuttle runs every 30 minutes, but today there were enough folks that it ran continuously...it was busy but not at all crowded....
I love doing things I could never do when I lived up North....