This antebellum mansion was home to Major Robert Gamble and headquarters of an extensive sugar plantation. It is the only surviving plantation home in South Florida (just south of Tampa).
I believe that is a large cistern to the right, since there is a pipe coming from the roof and it is filled with water.
@soboy5@pennystot@kwind@mittens Thanks so much for your wonderful comments. I understand that there are many weddings and photo opps here. We were a mile away sitting in a parking lot when I discovered it with an app called History Here.