There are more ways to have fun in the Keys than there are Keys. Biking, diving, and kayaking, Bruce Stutz joins the playful land and sea creatures of Florida's far shores

A lone highway connects this watery realm to the terra firma of the Florida peninsula, but a highway can only do so much. In every other way, the Florida Keys remain a place apart.

I find this out barely an hour from Miami, just before the Card Sound Bridge, the northern and more scenic entry to the Keys. Drawn by the pickup trucks and four-by-fours parked on the shoulder, I pull over. WHERE IT'S LIKE LIVIN' IN A POSTCARD, the sign says, luring me into Alabama Jack's. There's no door, so it's easy. A roofed dock with wooden tables and a well-elbowed bar, it does bear the patina of authenticity. The ceiling fans are old airplane propellers. A foot-stomping fiddler drives the live rockabilly band. Bottled-beer drinkers banquet on platters of fish, shrimp, fresh crab, and crisp-fried conch fritters. These are not beach people, they're water people—fishing people with red necks and tanned arms. The place is so noisy that my waitress introduces herself by writing her name on my napkin. At one table, a group of people have discovered that food falling between the cracks in the floor brings a frenzy of fish below.

I'm looking out toward nothing but water and wooded islands. White herons fly among them. Red-winged blackbirds peck at crumbs on the empty table next to mine. Alabama Jack's is the terminus and the portal. One more beer, one more song, and I'll be ready to cross to the other side.

Put together all the dry land in the Florida Keys and you end up with barely a thousand square miles—half the size of Rhode Island, divided among two hundred islands. Key Largo, the northernmost and largest key, is a mere twelve square miles of land a scant six feet above sea level. Yet the reef just off its eastern shore covers eighty square miles—and is part of the third-longest coral reef in the world. The marine sanctuary that encompasses the reefs and waters here totals 3,600 square miles. This is a place where water looms larger than land.

Beyond the bridge, on the road through the northern half of Key Largo, I get a glimpse of what the Keys looked like before the highway. It's a rare sight to see. These are tropical hardwood hammocks—hammocks being small islands, often no more than limestone mounds just far enough out of the water to allow trees to root. The hardwoods are species with names that evoke their Caribbean origins: sabal palm, gumbo limbo, coco plum. Many of these broad-leaved trees no longer exist elsewhere in the Keys, but here they form dense thickets as sultry as miniature rain forests. Crocodiles, more shy than alligators, thrive in them. Just off the road lies Crocodile Lake National Wildlife Refuge, where what's left of this sensitive environment is closed to human traffic. So despite the fact that I'm here at the height of crocodile breeding season, the goings-on will have to be left to my imagination.

Bayberry and mangrove edge the road, and I roll down the window as I drive to enjoy the fragrance and the silence. But all too soon I reconnect with Route One and its billboards, lime- and pink-colored shell shacks, T-shirt shops, tiki bars, trailer parks that rub shoulders with high-toned spas, and cement pelicans and manatees that are the Keys equivalent of lawn jockeys.