Time has dramatically carved the landscape of Kauai, the northernmost and oldest of the main Hawaiian Islands. It has a more rural and intimate feel than neighboring Oahu, and still teems with authentic Hawaiian culture and heritage. Lush and enchanting, many of the aptly named Garden Isle’s natural wonders are seen only by air or water, and myriad tours and backcountry adventures abound. A first stop for many visitors is the western Na Pali Coast, where snorkel, kayak, and sunset sailing cruises navigate the waters beneath steep, brilliantly hued mountain ridges framing waterfalls and deep valleys. Some boat tours visit sea caves and nearby Niihau, the Forbidden Island, or ply the Pacific in search of spinner dolphins and migrating humpback whales. Back on land, coursing down trails on a mountain bike is an exhilarating way to explore Waimea Canyon—the Grand Canyon of the Pacific—and neighboring Koke'e State Park. Head east to the serene Wailua River for kayaking and hiking among fern grottos and hidden waterfalls. Down south, fly through the treetops on a Koloa zipline tour. And then, of course, there are Kauai’s heavenly beaches—Hanalei Bay and Spouting Horn are two of the island’s most scenic. Come evening, head to Luau Kalamaku for Hawaiian cuisine and Polynesian entertainment. And don’t be fooled by Kauai’s small size: There is a lot to do, so a multi-day tour may be the best way to see it all—or if you’re short on time, a helicopter tour reveals Kauai’s natural beauty from above.