Hacienda Santa Ana is the home of Ron del Barrilito, one of Puerto Rico's most storied rum names and a worthwhile stop if you want Bayamón to be more than a pass-through suburb. The visitor experience focuses on the Fernández family estate, aging rooms, and the long continuity of a brand that has stayed closely tied to this site.
It is still a commercial distillery tour, so go for the history and tasting rather than expecting a museum in the strict sense. Paired with Bayamón's plazas and museums, it gives a useful glimpse of the industrial and agricultural side of Puerto Rican culture that rarely fits into a beach itinerary.