Paddling beside the 17-mile stretch of moss-smothered spine walls, shadowy canyons, and nearly illusory beaches on Kauai's north shore, you almost expect Al Gore to materialize on a cliff face, laser pointer waving, to remind you that this is why we must save our planet. Instead you get feral goats navigating razor-thin toeholds, sea turtles the size of Hummer tires surfacing in sapphire waters, and eight hours (or eight days) along some of the earth's most inspiring coastline.     

Kayak Kauai runs trips daily (except Sundays) throughout the year. [$95 for 5 hours; $1,750 for 7-day tour; kayakkauai.com]