Hubby and I are taking the 7/16/2006 Carnival Miracle Western Caribbean cruise. I balked for a day or 2 on signing up for the Selvatica zipline excursion and, when I looked again, it was gone [sold out, I guess]. I see an excursion called the Mayan Jungle Explorer; swimming in caves, 3 zipline trips and a 1 mile bike trek. Anyone out there take this? What did you think?