Try a trip on the "Sugar Train". It used to bring the cane to the processing plant but is now a tourist ride around most of the island. Takes several hours. You could also visit Romney Manor. It is the site of the island's beautiful botanical gardens and Caribelle Batik. The batik is pretty cool. They use an old process to dye fabrics and make clothing. My wife has several dresses from there. The Brimstone Hill Fort is pretty cool as well.

We spent several vacations there before coming to SXM and would go back in a heartbeat if the timeshares there were available thru RCI.