Because the Hyatt Kauai is such a handsome and well-managed resort, with decent food and plenty of activities for both kids and adults (lei-making workshops, luaus, water sports), the place is a breeding ground for resort lock. Isaac quickly joins a pack of kids and is more than happy to stay put. So while he plays volleyball in the pool and charges soft-serve cones at the snack bar, I take off for a 2 1/2-hour tour of Poipu's wonderful Allerton Garden. We do manage to tear Isaac away for a two-mile hike to Waipoo Falls along the precipitous lip of Waimea Canyon, through a stark red-desert landscape that could not have contrasted more sharply with Napali's lushness (the relatively arid western side of Kauai looks uncannily like the American West, with plunging canyons, pastel geology, and sublime prospects). But we almost surely would be pinned down at the Hyatt for the rest of our vacation had we not already made a reservation to go on that zip-line safari, an expedition Isaac has been looking forward to all week.
My own expectations are not high (a zip-line safari?!), but our afternoon with Spot proves to be one of the most exhilarating of our trip. After a 10-minute hike in from the trailhead where Spot parks the van, we find ourselves at the bottom of Kipu Falls. Someone has rigged up an aluminum ladder on one side of the falls; the ladder meets a rope swing hung from a huge banyan limb high above. Spot nudges the adults in the group to "get outside your box" and make the leap, but most of us demur, preferring an unadventurous swim in the deep, cool pool below. Isaac, however, needs no prodding; he scampers up the ladder and, after a moment's hesitation, throws himself off the rock cliff. "The first time was hella scary," he confides later. "When you're falling your stomach rises in your torso and you go, 'Oh, my God, why did I do this?' You feel like you're going to fall forever. Then you're underwater and you say, 'Hey, I'm not dead!' That's when it starts to feel good. And then you say, 'I'm going to do it again!'" Which he does, again and again and again.
After an hour or so, Spot leads us downriver to the zip line, 100 yards of steel cable strung between a tremendous banyan and mango tree on either shore. Around the ancient tree on our side of the river Spot's company has erected an elaborate four-story structure of wooden platforms, linked by steps: the ultimate in tree-house architecture.
We don rock-climbing harnesses and helmets and mount to the highest platform, where Spot tests our gear. When my turn comes, he clips my harness to the zip line and asks if I want to go facing forward or backward. (Backward?!) All that is left to do now is jump. Out of a 50-foot-high tree. Spot convinces me that the rig is safe (it's been designed, built, and certified by something called the Association of Challenge Course Technology, which for some reason I find reassuring), but I guess I still have my box to climb out of.
Spot whispers exactly the right word of encouragement, and I duly proceed to jump, face-first. After a few nanoseconds of heart-stopping free fall, I feel the line suddenly seize up and throw me forward in a headlong Tarzan swoop across the river to a platform on the far shore. I can't quite believe this is me, flying like a big awkward bird, screaming like a complete idiot—but an ecstatic idiot. Hokey it may be, but zip-lining turns out to offer quite a rush—and not a bad way to be in these wonderful woods.
As we head back to the van, Isaac and Judith and I recapping the afternoon, I realize that Isaac is as proud of us for trying the zip line as we were of him for his intrepid Napali hike earlier in the week. "This has been one of my most perfect days ever," Isaac declares. And that is perhaps Kauai's greatest gift: the island's excellent adventures have aligned an 11-year-old's idea of the perfect day with our own.
MICHAEL POLLAN is a professor in the graduate school of journalism at Berkeley and the author of the best-selling The Botany of Desire: A Plant's-Eye View of the World. He is currently writing a book about the ecology of eating.