Book Harrison's Cave Tour here.
Harrison's Cave is a huge natural underground system charted as far back as 1760 but somehow was lost until heavy rains created an entrance just a few years ago.
The government quickly recognized what a unique attraction this would make, so it quickly built the Caribbean's first subterranean tram ride. This is a very well organized excursion.
After a slide presentation, you board a 36-passenger electric tram for an hour-long tour. Very effective use has been made of indirect lighting to magnify the eeriness and beauty of the caverns.
Most memorable are the several cascading waterfalls and the great Rotunda Room, a 250-foot-long by 100-foot-high chamber glistening with cream and white geologic formations.
Tours are given every day on the hour, but since long lines can form, this is one place you do need advance reservations.