Following an extensive refurbishment, the centuries-old Baños de Coamo have the air of a modern spa, with handsome changing rooms, piped-in jazz and a small cafe. It’s doubtful you’ll have a tranquil soak due to the close quarters, but for thermal waters aficionados it is certainly worth a detour. Swimsuits are required – bathing au naturel isn’t tolerated.
The upper pool has thermal water at about 110°F; the lower one is cooler. It's a very agreeable spot to soak away the stress of driving Puerto Rico's roads. Custodians will stress that you shouldn't spend above 15 minutes at any one time in the hot pools – after this period, you should take a break to cool off.
The thermal baths are found by following Rte 546 down from Hwy 153 to its end by a small river.