Eighteen hours earlier I'd pressed my face against the glass of that very same bush plane. From 1,750 feet above the Arctic coastal plain I could see the past, present, and future scroll below the Cessna winging east from the Happy Valley airstrip. The tundra was scored with weird geometric shapes--centuries-old ice wedges, ice-filled earthen mounds called pingos, thermokarst lakes trapped atop permafrost craters. I watched the plane's shadow glide across Fin Creek and the Ivishak, Kavik, and Echooka Rivers, the last one a braided plain of gravel choked with a frozen skim of aufeis. And then there was the future, at least in the short term: the glacier-fed Canning River, hemmed in by cliffs 3,000 feet high. During months of discussing logistics with bush pilots, biologists, and locals, one location came up time and time again. If you have only one float trip to make, I was told, make it on the Canning. Flowing down the western boundary of the Arctic National Wildlife Refuge, the Canning held the promise of Arctic char on the line and big flocks of willow ptarmigan.