I was turning 30, and I wanted to celebrate. That's why I picked Barbuda, sister island to Antigua and known as much for its sand as for its pampering. But the truth is, I got restless after one lazy day at the beach. I had heard others discussing the rainforested lushness of Darby Cave, which was close to the resort where I was staying, The Beach House at Palmetto Point. So I hired a guide, Fabian, to take me there.