Where do you draw the line on national park boundaries? They long have been political creatures, with no regard to traditional wildlife corridors, viewsheds or, in some cases, common sense.

This question comes up all the time. Most recently it's a question in play at Acadia National Park and Valley Forge National Historical Park. Truthfully, there are probably relatively few parks where this question is not worth debating. But where it is, how do you answer it?

At Valley Forge, the answer is being hashed out in public between the National Parks Conservation Association, the Coalition of National Park Service Retirees, the National Park Service, and the American Revolution Center. The crux of the matter is 78 acres of land bounded on three sides by the historical park and which the Park Service long has coveted, but has not been able to afford. In steps the American Revolution Center, which wants to build a museum and educational center at the least on the property.

At Acadia, there was an attempt last year to develop roughly 20 acres on the northern slope of Acadia Mountain. The development was possible because back in 1986, when the park's lines were aligned, its namesake mountain was, in effect, split in half between public and private property. Fortunately, Friends of Acadia came to the rescue by organizing a drive to raise $1.75 million to buy out the development and see that the acreage will be preserved as open space.

However, now there's another development poised to be planted on Acadia's borders. In this case the development is proposed to run near the park's Schoodic Point extension, which is off to the east of Mount Desert Island across Frenchman Bay. What's being proposed, according to news reports, is an "eco-resort" of some 3,300 acres.

"My initial reaction is one of great concern. Any development is going to have tremendous impact on the park," Acadia Superintendent Sheridan Steele told the Bangor Daily News.

Looking at the map, though, no doubt would lead some to believe this proposal is no big deal. It's not as if the development would run shoulder-to-shoulder with Schoodic Point. Of course, a 3,300-acre development has the potential to exert quite a few impacts on its neighbors in terms of congestion, viewsheds, and supporting infrastructure.

So where do you draw the line? Should more effort be put into preserving wildlife corridors, such as those that run from Yellowstone National Park on north to the Yukon? Should the Park Service only be concerned with "in-holdings," those parcels of private land located completely within the boundaries of a national park? Should it not even worry about private lands, but focus entirely on those acres currently within the national park system?

These are tough questions, particularly in light of the federal government's budgetary resources. But as the saying goes, they're not making wilderness any more.