Stecoah Gap sits, at 3,165 feet, in a high saddle in western North Carolina's Cheoah Mountains. It's a quiet place - a weatherbeaten, two-lane state highway crosses the mountains in the gap, amid a thick tangle of hardwoods, wildflowers, and the white-blazed footpath of the Appalachian Trail. Black bears lumber across the road from time to time. Brightly-colored salamanders scuttle underfoot.

But Stecoah Gap is getting attention not for what lives in its forests and nearby coves, but for what lies beneath. Last year, the North Carolina Department of Transportation released its plans to drill a 2,870-foot long tunnel almost 500 feet below Stecoah Gap, as part of a project aimed at building a mostly four-laned highway across the southern Appalachian highlands of North Carolina and Tennessee.

Deemed Corridor K, the road-building project is part of the larger Appalachian Regional Commission's Appalachian Development Highway Program, authorized by Congress in 1965 to build modernized highway systems throughout the Appalachian Region. The ARC's highway system stretches from New York to Mississippi, and its component roads (or ‘corridors') are named with letters from A to X.

The highway programs' corridors are mostly complete, except for a few scattered segments throughout the region. (Map here.) The section of Corridor K through Stecoah Gap is one of these unfinished pieces, and the Department of Transportation's release of a Draft Environmental Impact Statement in 2008 firmly stated its resolve to go forward with making Corridor K complete. Their plans call for a four-lane highway to climb the Cheoah Mountains, travel under them via a tunnel drilled into the headwaters of Sweetwater Creek, and descend the other side through Locust Cove, one of the Appalachians' famous rich, north-facing cove forests.

To say that the ARC's highway system is a bit antiquated is an understatement. Designed in a time when the threat of a nuclear attack - and the need for evacuation routes out of major cities - was a real concern, the system's corridors were created to pierce the isolation that had plunged the Appalachians into poverty and left them ignored by the creation of the nation's interstate highway system. That isolation has been broken in today's increasingly wired world, and the southern Appalachian people now bank on the mountains' isolation and beauty for the tourism dollars they generate. The Corridor K proposal has been met with a huge amount of public criticism, not just because of the threats it poses to the region's wildlife but because of debate over how much benefit it would actually have.

Do we really need an expensive network of highways through one of the East's most rugged and diverse regions? And if we do, will its economic benefits outweigh its costs, both monetary and environmental? These are questions that need asking before such roads are built - not after the tunnels have been blasted and the forests paved over. Finding their answers will take approaches as unique as the mountains themselves, and in the end, may prove more difficult than building roads ever could be.