Unearth The Voyage
America’s national parks cover more than 85 million acres of mountains, forests, canyons, and backcountry wilderness. Their scale is part of what makes them so remarkable, and also what makes them so difficult to search when someone goes missing. Over the decades, visitors have vanished after separating from hiking groups, setting off alone, or simply stepping away from a campground. Some cases produced a single clue.
Others produced nothing at all. The 14 cases below all involve real people who disappeared within actual U.S. national parks and whose whereabouts have never been confirmed. Each story is different in its details, but they share a common thread: extensive searches, limited answers, and questions that remain open years or even decades later. Understanding these cases offers a sobering reminder that even well-traveled parks contain vast stretches of wilderness where finding one missing person can become an enormous challenge.
1. Dennis Martin in Great Smoky Mountains National Park
On June 14, 1969, a six-year-old boy named Dennis Lloyd Martin walked into the woods near Spence Field in Great Smoky Mountains National Park and never came out. He was camping with family members when a group of children hatched a plan to hide and surprise the adults. Every other child reappeared as planned. Dennis did not.
The search that followed was one of the largest in the park’s history, drawing hundreds of volunteers and professional searchers across the surrounding mountains. Despite the effort, investigators never recovered a confirmed trace of the boy, not a shoe, not a piece of clothing, not a single footprint beyond the last known location.
Dennis has remained missing for more than five decades. Authorities have generally concluded that he became lost and did not survive the terrain, but no physical evidence has ever confirmed that theory.
2. Cian McLaughlin in Grand Teton National Park
Cian McLaughlin entered Grand Teton National Park through the Moose Entrance station on June 8, 2021, at approximately 2:15 p.m. The 27-year-old snowboard instructor, who held dual Irish and American citizenship, was wearing a cutoff tank top, shorts, and a bucket hat, and was not carrying a backpack. His phone last registered a signal near Cottonwood Creek around 3:30 p.m. that afternoon.
When McLaughlin failed to show up for work on June 10, concern mounted. His vehicle was found at the Lupine Meadows Trailhead on June 13. Ground crews, aircraft, and dog teams searched areas including Garnet Canyon, Delta Lake, and Surprise and Amphitheater Lakes, but no trace of him was found.
A false sighting report from a local woman later diverted search resources and resulted in a court order requiring her to pay more than $17,000 in restitution. McLaughlin remains missing.
3. Jonghyon Won in Grand Canyon National Park
Jonghyon Won’s white Toyota Camry was found abandoned at Moran Point on the South Rim of Grand Canyon National Park in September 2017. The 45-year-old Los Angeles resident had no known plans to visit the park, and investigators found no record of him arranging a hike or camping trip in the area. The vehicle had previously been spotted near the New Hance Trailhead.
The New Hance Trail is one of the most technically demanding routes into the canyon, with steep, unmaintained terrain and no reliable water sources for long stretches. Searchers examined the surrounding area but found no physical indication of where Won had gone after leaving his vehicle.
Won was described as 5 feet 7 inches tall and 121 pounds, with black hair and brown eyes. He has never been located, and his case remains unresolved with no confirmed explanation for his presence at the canyon or his subsequent disappearance.
4. Thelma Pauline Melton in Great Smoky Mountains National Park
Thelma Pauline Melton, known to friends as Polly, was not a stranger to the trails around Deep Creek. The 58-year-old had hiked the area many times and knew the route well, which is part of what made her disappearance on September 25, 1981 so puzzling. She was walking with two friends, Trula Gudger and Pauline Cannon, when she picked up her pace and moved ahead of them.
Her companions assumed she had simply returned to the campground where her Airstream trailer was parked. When she had not appeared by evening, a park ranger was notified. A search involving 150 volunteers and nine dogs failed to locate her. One dog tracked her scent to her last known position, then lost the trail entirely.
Park officials later suggested she may have left the park in a vehicle, but no confirmed sighting was ever established. Polly Melton has never been found.
5. George Penca in Yosemite National Park
George Penca reached the top of Yosemite Falls on June 17, 2011, along with roughly 20 members of a church hiking group. The 30-year-old was last seen getting water from Yosemite Creek near the summit of the falls around 2:40 p.m. The group planned to regroup and hike back together, but Penca never rejoined them. His friends initially assumed he had headed down early on his own.
By 9 p.m., when he still had not appeared, a missing-person report was filed. Yosemite launched one of its largest search operations, involving approximately 140 personnel, helicopters, ground crews, and tracker dogs equipped with GPS devices. After nearly a week of searching, not a single footprint or piece of physical evidence had been found.
Penca was not considered an experienced hiker, and the terrain near the top of the falls is steep and unforgiving. He remains missing to this day.
6. Sam Bharat Dubal in Mount Rainier National Park
Sam Bharat Dubal planned a hiking and camping trip to the Mother Mountain area of Mount Rainier National Park in October 2020 and was expected home the following day. The 33-year-old was regarded as an experienced hiker who had prepared carefully for the conditions. He carried overnight gear, rain and snow equipment, a phone, and a charger before setting out.
When he did not return as expected, a search was launched. Teams spent approximately two weeks covering the terrain around his planned route without finding any physical evidence of his location. The October conditions in that area of Mount Rainier can shift quickly, with snow, cold temperatures, and limited visibility creating significant challenges for both hikers and search crews.
Dubal remains classified as a lost or injured missing person. His case is one of several recent disappearances in Pacific Northwest national parks where extensive searches have concluded without a confirmed answer.
7. Michael Ficery in Yosemite National Park
Michael Allen Ficery had hiked Yosemite’s backcountry before, which made his planned solo route near Hetch Hetchy Reservoir in June 2005 seem well within his abilities. The 51-year-old’s itinerary included Rancheria Falls, Tiltill Mountain, Lake Vernon, and Beehive. His permit expired on June 19, and when family members had not heard from him by June 21, they called the park service.
Searchers eventually found his backpack near Tiltill Mountain, off-trail in terrain described as extremely rugged and hazardous. Missing from the pack were a water bottle, a camera, and a topographical map. No other trace of Ficery was ever recovered, not clothing, not equipment, not any biological evidence.
The National Park Service spent close to half a million dollars on the search, making it one of the most expensive operations in Yosemite’s history. Ficery has never been located, and no explanation for his disappearance has been confirmed.
8. Morgan Heimer in Grand Canyon National Park
Morgan Heimer was 22 years old and working as a commercial river guide when he disappeared beside the Colorado River on June 2, 2015. His group was near River Mile 213 in Grand Canyon National Park, and he was last seen standing on a low cliff close to Pumpkin Springs. When a fellow guide looked back a short time later, Heimer was gone.
His absence went unnoticed for several hours until he failed to appear for dinner that evening. A large search operation was launched, but the terrain along that stretch of the Colorado River made the effort enormously difficult. No trace of Heimer was found during the search.
He was considered a strong swimmer and an experienced outdoorsman, which made the circumstances even harder to account for. His case remains unresolved, and no physical evidence has ever clarified what happened at that stretch of river.
9. Dikran Knadjian in Yosemite National Park
Dikran Knadjian had arrived in the United States from England as part of a broader American vacation when he checked into Camp Curry Village in Yosemite National Park in July 1972. The 20-year-old Cambridge University medical student was last confirmed at the registration desk on July 24, where he asked an attendant for directions to Half Dome. He was wearing bell-bottom jeans, a polo shirt, and an orange Omega wristwatch, and was carrying a Pentax camera.
He never completed his planned trip to Florida, and no one reported seeing him after that brief exchange at the desk. Search efforts at the time produced nothing, and no physical evidence was ever recovered from the surrounding wilderness.
Knadjian’s family in England was left without answers. Decades later, his case remains listed as unsolved, with investigators believing he likely became lost or injured somewhere in Yosemite’s vast backcountry.
10. Floyd Roberts in Grand Canyon National Park
Floyd E. Roberts III set out on a nine-day group hiking trip on the Shivwits Plateau in the western section of Grand Canyon National Park in June 2016. The 52-year-old was an experienced outdoorsman who had visited the park before. At some point during the trip, Roberts separated from his companions, reportedly to take a different route around a hill before reaching the trailhead.
He was last seen near Kelly Tank, apparently heading toward Trail Canyon and the Colorado River. That week, the area was under extreme heat advisories, with temperatures approaching 120 degrees Fahrenheit. An extensive search of the surrounding terrain failed to locate him or establish the route he ultimately took.
No physical evidence was ever recovered from the area. Roberts remains missing, and his case stands as a sobering example of how quickly conditions in the western Grand Canyon can become unmanageable even for prepared hikers.
11. Trenny Gibson in Great Smoky Mountains National Park
A school field trip to a national park should be one of the more memorable days of a teenager’s year, but for Teresa Lynn Gibson, October 8, 1976 became something far more difficult to explain. The 16-year-old, known as Trenny, was among roughly 40 classmates hiking toward Andrews Bald in Great Smoky Mountains National Park when the group split into smaller clusters along the trail.
Trenny was last seen that afternoon near the Clingmans Dome area as the students made their way back toward the parking lot. She was never seen again. Searchers spent weeks covering the surrounding terrain without finding any physical evidence of where she went.
Her case remains classified as unsolved by the National Park Service, and no confirmed trace of her has ever been recovered, making it one of the park’s most enduring cold cases.
12. Barry Tragen in Glacier National Park
Barry J. Tragen’s vehicle was spotted near Kintla Lake in the remote northwest corner of Glacier National Park on July 22, 2020. The 68-year-old Columbia Falls, Montana resident did not return as expected, and rangers launched a search on July 25. The operation grew to include ground crews, dogs, aircraft, boats, and a remotely operated underwater vehicle.
On August 4, a pair of sunglasses believed to belong to Tragen was recovered from Kintla Creek. Search dogs showed interest near the outlet of Kintla Lake, but no additional physical evidence was found. The FBI and the National Park Service Investigative Services Branch both participated in the investigation.
On August 10, the search transitioned to limited continuous status, meaning active efforts would pause unless new information emerged. Tragen remains classified as a missing person, and no confirmed explanation for his disappearance has been established.
13. Ruthanne Ruppert in Yosemite National Park
Ruthanne Ruppert was last seen around noon on August 14, 2000, near the Curry Village area of Yosemite National Park. The 49-year-old had been treated at the Yosemite Medical Clinic for an eye infection shortly before she disappeared. She had originally planned a backpacking trip but postponed it due to her illness, and investigators believed she may have attempted a day hike from Yosemite Falls toward the Foresta area instead.
For eight years, the case produced no physical evidence. Then, in 2008, her backpack turned up in the Fireplace Creek drainage, along the route she was thought to have taken. The discovery confirmed a general direction but revealed nothing more specific about what had happened.
Ruppert was never found, and her case remains open. The eight-year gap between her disappearance and the recovery of her backpack added an unusual layer of difficulty to an already complicated investigation.
14. Patrick Whalen in Glacier National Park
Patrick Terrence Whalen was 33 years old and had spent considerable time hiking and camping in wilderness areas before he disappeared in the Glacier National Park region in 2000. His experience level made the disappearance particularly difficult to explain. He was not someone unfamiliar with remote terrain or the demands of backcountry travel.
Months after he was reported missing, a park ranger came across an abandoned campsite near Atlantic Creek. Personal belongings found at the site were identified as Whalen’s, confirming that he had been in the area. The campsite offered a geographic reference point, but it answered very few of the larger questions surrounding the case.
Searches of the surrounding wilderness did not locate him. Investigators were never able to establish where Whalen went after leaving that camp, and his disappearance remains one of Glacier National Park’s unresolved missing-person cases with no confirmed outcome.
