PATTEN, Me. — Lucas St. Clair pulled up to an overlook in Maine’s North Woods to a stunning vista of Mount Katahdin, the state’s highest peak and the endpoint of the Appalachian Trail. Stretched out below was a vast green carpet of pine and spruce flecked with golden aspens and blazing red maples; Millinocket Lake glistened in the distance.

“I think it’s national-park worthy,” he said.

This was not an idle observation. Mr. St. Clair and his mother, Roxanne Quimby, who owns the land, have been trying for years to turn these woods into a national park. But ferocious opposition has stalled their plan, partly out of antipathy toward Ms. Quimby, who, against Maine tradition, closed off her lands to hunters and snowmobilers, and partly because many in this fiercely independent region loathe the idea of giving Washington a toehold.

Besides, it is actually hard to create a national park.

Consider this: Since Congress named Yellowstone the first national park in 1872, it has conferred this prized title on only 58 other sites. And most, including the Grand Canyon, received lesser designations, like national monument, long before they officially became parks. The most recent national park — Pinnacles, in California — was so designated in January, after being named a national monument in 1908.

The grand philanthropic gestures of families like the Rockefellers and Mellons, who helped build and expand the national parks, are now few and far between, and even for them it was not always easy. John D. Rockefeller Jr. spent three torturous decades trying to overcome local opposition so he could add land to Grand Teton National Park.