When Meriwether Lewis and William Clark voyaged into history almost 200 years ago, their journal entries paid special homage to a cluster of sandstone cliff formations flanking Montana's upper Missouri River.
Among the surreal landforms that greeted them as they threaded their westerly route to the Pacific Ocean was a prominent white arch standing sentinel hundreds of feet above the river valley. The formation was later named the Eye of the Needle.
But this spring, the geological marvel that had taken nature millennia to sculpt, was turned to rubble in a matter of seconds by vandals.
"Even people who have never been to the upper Missouri feel the loss because they know a piece of history is gone forever," says Craig Flentie, spokesman for the federal Bureau of Land Management (BLM), which oversees resource protection along the remote river corridor. "It is a reminder of the shortsightedness - and some say vicious - side of society."
Federal resource caretakers note that the wanton destruction at Eye of the Needle underscores a growing problem of vandalism on public lands in the United States. While some parks have met with success by recruiting civilians to help safeguard their treasures, problems continue to escalate.
From gun enthusiasts who have used ancient Indian petroglyphs for target practice, to outlaw Civil War buffs who have looted artifacts from hallowed battlefields, treasures in the outdoor vault of antiquity are disappearing.
The US Forest Service expects the number of incidents on its 191 million acres to climb well beyond the record 503 cases chronicled last year. The National Park Service, confronting a similar gamut of problems from graffiti in urban parks to thefts of Anasazi pottery in Southwest preserves, may have to investigate 10 times that number. And the BLM, which administers 268 million acres - most of it in the archaeologically rich interior of the West - is bracing for an onslaught of its own land.
Yet few cases carry the emotional weight of Eye of the Needle. Reclining in their camp at Eagle Creek on May 31, 1805, Lewis and Clark gazed across the Missouri toward the 11-foot archway.
For those tracing their paths in modern times, the icon was considered as synonymous with this legendary section of the "Mighty Mo" as certain monuments are to the Mall in Washington.
Given the Eye's celebrated stature, the US Justice Department sent a geological forensics expert and offered the services of the FBI to assist in the investigation. So far, despite a growing pool of reward money, no arrests have been made.
Initially the BLM intended to repair the Eye, says Mr. Flentie, but based on an outpouring of 700 citizen comments from across the country, a consensus emerged to leave it in a ruined condition.
"The message was that it cannot be rebuilt," he says. Instead, a copy of the Eye, based on extensive photo records, is slated to be erected in nearby Fort Benton in time for the Lewis and Clark bicentennial celebration six years away.
Meanwhile, the BLM is calling on the public to help protect other wonders along the river since vandalism nationwide shows no signs of abating.
Indeed, the general public's desire to make sure that their public lands are not vandalized has been some parks' greatest asset. After budget cuts depleted their staff, park rangers at Gettysburg National Military Park in Pennsylvania were being overrun by vandals. But citizen volunteers, enlisted through a program called Park Watch, mobilized a legion of civilian sentries and since then, losses have dropped dramatically.
Yet despite stepped up law enforcement and public vigilance, vandalism remains all too prevalent. This year, officials at the Petrified Tree National Park in Arizona project that visitors will walk off with nearly 12 tons of stony tree trunks, denuding portions of the landscape of its very attraction.
"The majority of theft is not occurring by people who load up the back of their pickup trucks and drive away," notes Pat Quinn, the park's chief ranger. "Most of it disappears in the form of small chunks that are taken home. Although it might appear insignificant, every little piece adds up."
But guilty consciences weigh heavily. Purloined tree parts are mailed back weekly. And near the park exit stations, where road signs warn that vehicles may be searched, piles of debris accumulate as visitors dump their booty before reaching the checkpoint.
The increased vandalism, some say, means more than just physical damage - it could signal an end to the time when Americans had almost unlimited access to public landmarks and geological relics.
"Like everyone else, I feel an emotional and intellectual connection to the world when I can walk among the resources - whether it is Eye of the Needle or a forest of petrified trees," says Mr. Quinn. "The vandals who step over the line are ruining it for people they don't know, and they're depriving their own descendants of a more meaningful life."