Most people who cross the Atchafalaya Basin on Interstate 10 are staring at their phone or counting the miles to New Orleans. You drive out onto what feels like an endless overpass, water spreading out on both sides as far as you can see, cypress trees rising out of the brown water below — and then, about 18 miles later, you're back on dry land, wondering what just happened. What just happened is that you crossed one of the most extraordinary places in North America.