The short swim from a swimming hole through a narrow gorge to a powerful waterfall is charmingly spooky; it's dark down there with steep vine-clad lava walls no more than 5ft or 7ft apart. It's an ethereal and unusual place, but can get crowded. If there's a cruise ship in port, come early or late in the day for relative serenity.
The name, by the way, is Creole for 'small throat.' Don't swim the gorge after heavy rains when dangerous flash flooding may occur. Scenes from Pirates of the Caribbean were filmed here.