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A Great Smoky Mystery: What Happened to Trenny Lynn Gibson?

This case has remained unsolved for 47 years, 1 months, and 30 days.

Trenny Lynn Gibson was excited to go on a field trip with her horticulture class on October 8, 1976. The weather was a bit dreary, but that didn’t mean they couldn’t take their nature hike through the Great Smoky Mountains National Park. The class was to hike to Andrews Bald, a scenic are of high elevation and grasslands. 

The students went off on their hike, with many seeing Trenny during it. However, when it was time to return to the bus to get back to campus, Trenny was nowhere to be found. Searches were conducted for the missing 16-year-old but nothing of her has ever been found, even nearly five decades on. What happened to Trenny Gibson?

Table of Contents

About Trenny Lynn Gibson

Trenny Lynn Gibson was born on August 17, 1960 to parents Robert and Hope Gibson. Some news outlets incorrectly report that her name was Teresa, but her given name was Trenny and there was a mistake in the original park service report. She had some siblings, too: a brother and a sister.

Unfortunately, I couldn’t find too much information about what Trenny was like or her interests, but I managed to find a few comments here and there. “She would listen to Jethro Tull and hang out and… just be kind of Trenny,” said high school friend, Kim Pouncey. 

A photograph of Trenny Lynn Gibson.
A photograph of Trenny Lynn Gibson (Strange Outdoors).

Trenny worked at a cafeteria in a local mall in addition to attending school, and it’s said that she was very careful with her earnings and put most of her money into a savings account. She also was interested in landscape architecture and hoped to one day to study at the University of Tennessee to get a degree there.

Somewhat Small in Stature

By the time Trenny was 16 years old in 1976, she was about 5’3 and weighed around 115 lbs. She was a small teenager and I mention this information only because it may have played a part in her disappearance (if she was indeed abducted or perhaps even attacked by a predator). 

Overall, Trenny seemed to be a pretty normal teenager for the time, with friends and a job and interests of her own. That all changed when she ended up missing from Great Smoky Mountains National Park in October 1976.

About Great Smoky Mountains National Park

In order to understand this unsolved mystery better, it’s important to understand the geography of Great Smoky Mountains National Park (GSMNP), sometimes known as the Smokies to locals. This park spans two states, Tennessee and North Carolina, and straddles the border between the two running southwest to northeast. It encompasses a vast 522,419 acres — a total of 816.28 square miles.

A view of the Great Smoky Mountains.
A view of the Great Smoky Mountains (Wikipedia).

The GSMNP is well-known for its waterfalls, mountains, biodiversity, and forests. The Appalachian Trail also passes through the Smokies on its path from Georgia to Maine. The park has been designated as a UNESCO World Heritage Site and an International Biosphere Reserve

All this is to say that the area is by and large a vast, untamed wilderness. Estimates claim that the park is almost 95 percent forest, making any search and rescue attempts very difficult because of the thick trees and hazardous terrain.

A Potentially Dangerous National Park

In 2022, GSNMP was ranked #5 in a list titled America’s Deadliest National Parks with a total of 113 deaths in the park from 2007–2021. According to the list, the most common cause of death is motor vehicle crashes. Park officials have also stated that they average about 100 search and rescues each year for missing persons, and in 2022, they recorded 11 deaths in the park.

I’m not trying to dissuade anyone from visiting GSMNP; rather, I’m trying to illustrate that caution and common sense is required when visiting not just this park but any national park. It’s very easy to get lost in the green depths of the forests and not be able to find your way back. Recall too that this article is about someone who may have gotten lost in the park and, to this day, has never been found.

The Day of the Disappearance

Friday, October 8, 1976 was the date of a field trip for students from Bearden High School in Knoxville, TN. They were headed to the Great Smoky Mountains National Park to see Clingmans Dome and hike to Andrews Bald (a bald is an area of high elevation and grasslands), although the students wouldn’t know that until they got on the bus. The planned hike was roughly 3.6 miles roundtrip and is generally accepted to be a moderate hike.

Autumn leaves in Great Smoky Mountains National Park.
Autumn leaves in Great Smoky Mountains National Park (Wikipedia).

At the time, Trenny was a 16-year-old sophomore taking a horticulture class in school taught by Mr. Dunlap. He was the same teacher who was taking the approximately 40 students on the field trip that Friday. Unfortunately, the weather was poor — dark and rainy — but the students and teacher were going anyway.

Arrival at GSMNP

Once the bus arrived at the Clingman’s Dome parking lot, the students were greeted by the famous Clingman’s Dome Observation Tower and the concrete trail leading up to it. The tower is the highest point in GSMNP and provides 360° views of the surrounding area — when the weather allows.

Clingman’s Dome Observation Tower in Great Smoky Mountains National Park.
Clingman’s Dome Observation Tower in Great Smoky Mountains National Park (NPS).

Before the students were let off the bus though, they were given instructions for the trip: hike to Andrews Bald, observe the plants and trees, and be back at the bus no later than 3:30 PM. Students were also told not to go off on any other trails or to go any further than Andrews Bald. Once the teenagers confirmed confirmed that they understood the rules, they were sent off on their journey.

The Hike

Several students reported seeing and walking with Trenny during the hike to Andrews Bald. Despite the chilly weather, everyone seemed to be having a good time. Trenny hiked all the way to the bald with a classmate she’d sat next to on the bus, but left his company to hike back to the bus. 

Another group of students was on the trail and reported seeing Trenny on their way back. She joined them for a little while, but when they sat down to rest, she continued on alone. The group was about a half to three-quarters mile away from the parking lot at this point in time.

And Then She Was Gone…

Once Trenny left the group she’d been walking back with, no one saw her again. That was around 3 PM. Some of the students looked around for her or for any side trails she might’ve gone down, but they saw no signs of her. Figuring that she’d likely be at the bus waiting for all of them, they continued on back to the parking lot.

By 3:40 PM, ten minutes after the deadline to return to the bus, people noticed that Trenny wasn’t there. Mr. Dunlap and another student made the hike back to Andrews Bald in search of her, but they too found nothing. The National Park Service (NPS) was contacted at 4:30 PM to report Trenny as missing.

The Search Begins

Authorities were quick to take Trenny’s disappearance seriously and immediately headed to GSMNP to start the search, bringing along many tools to help including scent dogs and helicopters

Dwight McCarter, a retired ranger and expert tracker who worked on Trenny’s case, said, “For some reason, she got ahead of the group coming back and wasn’t at the bus at the dome parking lot.” That was about all the information that police had when they started looking for Trenny. Unfortunately, the weather didn’t help with their desperate search.

The rainy, foggy weather in the Smokies made the search for Trenny a difficult one. Helicopters were unable to be sent out to search until the afternoon when the weather cleared up a bit. All the same, they didn’t spot any sign of Trenny.

Search Dogs Used

Authorities brought in search and tracking dogs in order to try to pick up Trenny’s scent. McCarter, the expert tracker, said in a television interview:

“Three of the dog teams followed her to the Appalachian Trail and followed her around the [Clingman’s Dome Tower]. Now, the dogs said that she walked right by this tower with all these people and the dog says she came out on this road about a mile away.”

Dwight McCarter (Source: WBIR Channel 10)

However, it seems that no one in the tower noticed Trenny walking around down below them. It’s possible that they didn’t see her, but it’s also possible that she was trying to stay out-of-sight. The scent trail ended along a roadside, which perhaps indicated that she’d made it to the road and then had been picked up by someone — or maybe even that she’d been forcibly dragged to the road. No one could say for sure.

Cigarette Butts and Beer

Some cigarette butts and a partially-full beer can were found near the spot where Trenny disappeared into the forest. More butts of the same brand were found near the road where the scent dogs lost the trail. It’s not clear if these items are related to Trenny’s disappearance, or if they are still being kept in evidence. 

Some of Trenny’s Items Left Behind

Back home, Trenny had left her purse, bank book, makeup, clothing, and cash behind. There was also $1,000 in her bank account which was never withdrawn. If Trenny had been planning to run off, wouldn’t she have taken some of these items with her?

Other Items Found

One of Trenny’s belongings — a comb — was located in the car of a fellow student who’d gone on the field trip. Trenny had sat next to this student, a close friend of her older brother, on the bus ride to the Clingman’s Dome parking lot. Police ultimately concluded that Trenny had given this student the comb to hold onto for her until the end of the field trip.

Trenny Gibson had a comb of a similar style to the one displayed here that she took everywhere with her.
Trenny Gibson had a comb of a similar style to the one displayed here that she took everywhere with her (CanadianGurl77).

What’s somewhat stranger is that Trenny had a star sapphire pendant and ring, gifts given to her for her birthday and Christmas presents. The pendant and ring were discovered in the possession of a girl from Bearden High School, and the girl couldn’t explain how she got them. 

Strange Incident a Few Years Prior

Trenny’s parents, Robert and Hope Gibson, reported that there had been an incident a few years earlier in which another student from Bearden High School had attempted to break into the Gibson’s home. Robert shot the intruder in the foot, stopping the invasion, and the intruder was sentenced to serve time in a juvenile correctional facility. 

When the intruder was in the courtroom, he’d made threats against Trenny, saying he’d harm her once he was out of juvenile detention. The student was back at the high school at the time of the field trip, making the family concerned that he might’ve done something to Trenny that day. However, the principal determined that the student had been attending classes on the day she disappeared, so he was largely ruled out as a suspect.

At some point, the FBI was called in to assist in the search for Trenny. They interviewed students at Bearden High School, hoping to hear or learn something that might guide them toward where the 16-year-old had gone. According to some sources, many of the students thought that Trenny might’ve run off with someone, although they weren’t sure who she could’ve ran off with.

The Aftermath

I remember coming into school that Monday and finding out she was missing,” said high school friend, Kim Pouncey. The desk where Trenny once sat apparently remained empty for some time, with neither teachers nor students knowing if she’d ever return. People also questioned why there was only one adult chaperone for a field trip with about 40 students.

The extensive searches of GSMNP continued until the end of October 1976. The Gibsons tried to keep their family together after Trenny’s disappearance, but they ultimately succumbed to the stress and her parents ended up divorcing

A memorial at Bearden High School for Trenny Lynn Gibson.
A memorial at Bearden High School for Trenny Lynn Gibson (CanadianGurl77).

Theories on What Happened

There are several plausible theories about what happened to Trenny Gibson on that fall day in October 1976. As is so often in cases like this, there are some that suggest outlandish things like alien abduction, but I’ll stick to the more realistic theories. 

Trenny Was Abducted

Many believe that Trenny was abducted while in GSMNP. Some even suggest that she’d somehow been captured and held against her will in the observation dome while searchers were looking below. The dome was not searched at the time. Another abduction theory is that she was forcibly taken and dragged through the forest to the road where the scent dogs lost the trail. Because Trenny was small in stature, it’s believed that she could have been easily carried off.

There is some evidence to support this theory. Remember that cigarette butts were found near where Trenny is thought to have gone into the woods, with more of the same brand found along the road where the search dogs lost her scent. Some people suggest this indicates that there was an abductor who grabbed her from the trail and took her to the road where there was a car waiting to take them away. 

Trenny Ran Away

Some have suggested that Trenny used the field trip as a way to cover her running away from home. “I’ve always felt like Trenny planned it and that was her way out,” said one of the people she went to high school with. I wasn’t able to find any information about who she might’ve run away with, or why, but it’s entirely possible that she was able to sneak away during the field trip to start anew.

Trenny Gibson’s photograph (center) in her high school yearbook.
Trenny Gibson’s photograph (center) in her high school yearbook (WBIR 10 News).

Trenny Succumbed to the Wilderness in the Smokies

It’s entirely possible that Trenny wandered off, got lost, and ended up succumbing to the elements. The average low temperature in October for the Smokies is 40.8°F, plenty cold enough for someone to end up with hypothermia. Nights are often colder, dipping down into the 30s. Damaging winds too are possible, with some gusts getting up around 80–100 MPH. The cold weather certainly could have been a reason for Trenny’s demise.

There’s also the possibility that Trenny got lost and then met with a predator, like a black bear. According to the National Park Service, approximately 1,900 black bears live in the Smokies, and some males can reach in excess of 600 lbs. come late fall. That is plenty large enough to attack — and kill — a small teenage girl. Other animals that may pose a danger to humans that live in the park include elk, bobcats, deer, and coyotes.

What Do I Think Happened?

Although I think that all of the theories are plausible in this case, the one that stands out to me the most is the idea that she wandered off and succumbed to the forest, be it the elements or a predator. 

Running Away Unlikely

Although some have speculated that Trenny used the field trip as an opportunity to run away, I’m not convinced that this happened. She didn’t take any of her belongings (like her purse or cash), nor was her bank account accessed ever again with her savings at the time. 

Additionally, the students attending the field trip didn’t know where they were going until they were on the bus that day. Had she planned an escape, would she have just gone along with wherever they happened to be going that day? Choosing a park like GSMNP to run away in is a daunting prospect, even if she’d originally planned to use the field trip as her escape.

If Trenny did run away that day, she would have had to start her entire life over again from scratch — which was possible in the 70s, but perhaps asking a bit much from a 16-year-old at the time.

Handwriting from Trenny Gibson in a Bearden High School yearbook.
Handwriting from Trenny Gibson in a Bearden High School yearbook (CanadianGurl77).

Abduction Possible

Many people point to the cigarette butts near where Trenny disappeared and the same brand on the road where her scent vanished as proof that someone took her. However, it seems unlikely to me that an abductor would 1) be waiting along a trail that is reasonably popular and busy, 2) would be smoking while waiting for the perfect target to cross their path, and 3) would continue smoking while forcing a struggling teenager into the car. 

It is possible? Sure. Is it likely? Not really. Furthermore, just because the cigarettes were the same brand doesn’t indicate that they were smoked by the same person. Data from 1974 shows that 37.1% of US adults smoked, and it’s very possible that several different people just happened to be smoking the same brand of cigarettes at different places in the park. Unless the found butts’ brand was extremely unusual, I’m not sure that I’m convinced they prove that Trenny was abducted.

The fact that the scent trail the tracking dogs picked up on ended at a road does suggest that abduction is possible and is more convincing to me than the cigarette butts found around the area. Of course, with so many people in the area that day (all the students on the hike, other hikers, and then searchers), the scent dogs could’ve gotten off-track following someone else’s trail. We’ll never know for sure.

Getting Lost Most Plausible

To me, the idea of Trenny wandering off and then getting lost seems to be the most plausible of the popular theories available. She was reportedly interested in landscaping and horticulture, so it doesn’t seem so crazy that she might’ve seen an interesting plant, wandered off into the forest to check it out, and then realized that she was lost. 

Trenny might’ve looked up and seen the Observation Tower at Clingman’s Dome and used that as a sort of guide, walking toward it (which would explain the dogs following her scent to the area below it). Instead of finding the right path back up to the tower though, she might’ve become lost, perhaps even wandering through the woods and ending up on that road the dogs lost her scent at. From there, anything might’ve happened to her. 

It’s also possible that Trenny wandered off into the forest and succumbed to either the elements or a dangerous animal somewhere out there. People go missing in national parks all the time; in 2017 alone, there were a reported 3,453 people who were reported missing from national parks according to the NPS Search and Rescue dashboard.

Case Outlook

Short of finding Trenny or her remains, I’m not sure that this case will ever be solved. It’s an incredibly sad situation where her family and friends have never received answers as to what happened to Trenny. If someone out there though does have information about Trenny’s whereabouts, they should come forward. It’s been over four decades and it’s time to bring Trenny home.

Case Updates

There have been some updates in the case of Trenny Gibson’s disappearance, but most of them are not good. 

April-May 1977: Another Search Conducted

Another search was carried out about six months after Trenny’s disappearance. However, they were unable to locate Trenny or her remains.

2000: Trenny’s Brother Passes Away

Trenny’s older brother, Robert Gibson Jr., passed away in 2000 at the age of 42. He never found out what happened to his sister.

2004: Trenny’s Father Passes Away

Robert Gibson Sr. passed away in 2004 at the age of 67, never knowing what really happened to his missing daughter.

2016: Trenny’s Sister Passes Away

In 2016, Trenny’s sister, Tina Gibson, passed away at the age of 54. Like the other family members, she never learned what happened to her missing sister.

Do You Have Information?

As of June 2023, the disappearance of Trenny Gibson is still classified as a missing persons case. At the time of her disappearance, Trenny was 5’3, weighed approximately 115 lbs., and had long brown hair and green or brown eyes. If you have any information that might help solve this mystery, please contact Great Smoky Mountains National Park at (865) 436–1230 or the Investigative Branch of the NPS at (888) 653–0009. 

A missing poster for Trenny Gibson.
A missing poster for Trenny Gibson (National Center for Missing and Exploited Children).

Cold Case Questions

  • Do you think Trenny Lynn Gibson left of her own volition or was she kidnapped?
  • Do you think Trenny is still alive today?
  • Will this case ever be solved?

Let me know your thoughts in the comment section below!

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2 thoughts on “A Great Smoky Mystery: What Happened to Trenny Lynn Gibson?

  1. Bear attacks are extremely rare. There are Panther,s that live in the mountains. Abduction or succumbed to the elements is my guess.

  2. Oh…I have been comparing her to Jane Does for years without any matches. I was 4 years old in 1976 but live somewhat close to that area and am from Western North Carolina

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