Marguerite Elizabeth Cardwell
Aliases: Marguerite Elizabeth Peterson, Marguerite Elizabeth Petersen
Missing since: September 16, 1973
Missing from: Canmore, Alberta
Date of Birth: September 3, 1942
Age at Disappearance: 31 years
Gender: Female
Ethnicity: White
Eye Color: Blue
Hair: Brown/Blonde
Height: 165 cm / 5ft 5in
Weight: 57 kgs / 126 lbs
Physical Build: Slender/Thin
Notable: Marguerite has multiple moles. She also has two 2in screws in her left ankle. Marguerite has a history of mental health issues and has attempted to take her own life in the past. DNA is available.
Marguerite Elizabeth Cardwell was 31 years old when she disappeared from Calgary, Alberta, in September 1973. More than half a century later, her case remains unresolved, leaving behind an abandoned vehicle in the foothills of the Rocky Mountains, a missing rifle, personal belongings that were never reclaimed, and questions her daughter would spend decades trying to answer.
According to the current Canada’s Missing record, Marguerite was last seen in Calgary on September 10, 1973. She told a friend that she was considering travelling either to Edmonton or Vancouver. Those destinations would have taken her in very different directions – Edmonton to the north and Vancouver to the west – but within days, the first tangible clue to her whereabouts appeared west of Calgary.
On September 16, Marguerite’s vehicle was discovered in the vicinity of Canmore. Later accounts place it more specifically near Dead Man’s Flats, a small community east of Canmore along the Trans-Canada Highway. Her purse and other personal belongings were still inside the vehicle. Secondary accounts based partly on research conducted by Marguerite’s daughter, Shelley Sawatzky, also report that the keys were left with the car.
There is a discrepancy concerning exactly when the vehicle was found. The current federal missing-person record gives September 16, while a description associated with Shelley’s later book gives September 18. With the RCMP currently using September 16, that is the date that appears to be the strongest one to use, while recognizing that older accounts differ.
The location of the car is interesting when compared with what Marguerite had reportedly told her friend. Dead Man’s Flats lies west of Calgary along the Trans-Canada Highway, meaning the vehicle was found in a direction consistent with the beginning of a journey toward British Columbia and eventually Vancouver. That does not establish that Marguerite was actually travelling to Vancouver, but it raises the possibility that she had begun the westward trip she had mentioned.
Then there was the rifle.
According to information later uncovered by Shelley, Marguerite had purchased a .303-calibre hunting rifle shortly before she disappeared. When her vehicle was found, the rifle was apparently not inside. There is no reliable public information establishing exactly when or where she purchased it, whether she also purchased ammunition, or whether anyone actually saw Marguerite carrying the rifle when she left Calgary.
Its disappearance nevertheless became important to the original investigation. Shelley later learned that investigators suspected her mother might have taken her own life somewhere in the mountains. Accounts of the investigation state that approximately 20 RCMP officers searched the surrounding area for two days.
They found neither Marguerite nor the rifle.
Publicly available information does not reveal exactly how extensive that search was, whether tracking dogs or aircraft were involved, or whether investigators found footprints, clothing or any other physical evidence leading away from the vehicle. What is known is that the search failed to provide the answer investigators were looking for.
The theory that Marguerite may have died by suicide appears in accounts of the historical investigation, and secondary sources report that she had previously experienced serious personal difficulties. However, the current Canada’s Missing entry does not classify her disappearance as a suicide. No body was recovered, and Marguerite remains officially listed as a missing person.
Years later, another detail emerged that complicated the picture.
As Shelley began investigating her mother’s disappearance herself, she located a woman who had lived in the same house as Marguerite. According to the woman’s recollection, around the time Marguerite disappeared, a man had been standing in the hallway outside Marguerite’s suite yelling at her.
Who was that man?
No reliable publicly available account identifies him. There is no confirmation that he was a boyfriend, friend, tenant, colleague or stranger. More importantly, it is unclear whether this information was ever given to police in 1973. There is also no evidence establishing that the confrontation had anything to do with Marguerite’s disappearance.
Still, it became another unanswered question surrounding her final known days.
Marguerite’s life was considerably more complex than the few lines preserved in her missing-person profile suggest. Records and possessions later examined by Shelley indicated that Marguerite had worked for law firms and oil-and-gas companies. She apparently held a Petroleum Ski Club membership and had even earned a flying licence while living in Montreal.
She was also reportedly managing a Calgary rooming house around the period of her disappearance.
There were conflicting stories about some aspects of her employment. One record connected Marguerite with a Calgary hotel, leading to a later claim that she had worked there as a topless dancer. A friend of Marguerite’s disputed that account and said she had actually worked at the hotel as a waitress. There is nothing establishing that her work at the hotel had any connection to her disappearance, but the disagreement illustrates how difficult it became for Shelley to reconstruct her mother’s life decades after the fact.
Shelley’s connection to the mystery was especially painful because she did not initially know that her mother was missing.
She had been placed for adoption when she was very young, although Marguerite reportedly continued visiting her periodically for years. Eventually those visits stopped. Shelley did not simply grow up knowing that her biological mother had vanished. Instead, she later began looking for Marguerite herself.
When Shelley was about 19, she discovered the truth: the mother she was searching for had disappeared years earlier.
That discovery began a search of another kind.
In 1993, approximately 20 years after Marguerite vanished, Shelley received a box containing belongings that had reportedly remained unclaimed from the Calgary property Marguerite had managed. Inside were photographs, employment records and other fragments of her mother’s life.
Piece by piece, Shelley began reconstructing the woman behind the missing-person file. She tracked down people who had known Marguerite, examined records and attempted to understand what had happened during those final days in September 1973. Her investigation eventually became the basis for her book, Missing from Dead Man’s Flats.
There was eventually one possibility that appeared capable of finally providing an answer.
In 1979, unidentified female remains had been discovered in the Banff area. Years later, investigators considered whether those remains could belong to Marguerite. When her case received renewed attention, Shelley supplied DNA for comparison.
It wasn’t her mother.
According to published accounts, Shelley’s DNA did not match the unidentified Banff woman. It also reportedly failed to match other unidentified remains available for comparison at the time. One possible answer had been eliminated, but Marguerite was still missing.
The case contains several frustrating gaps that have never been filled publicly. The identity of the friend Marguerite spoke with before disappearing has not been widely reported. There is no readily available description of the make, model or colour of her vehicle. The person who discovered it has not been publicly identified in the sources available today. The exact location where the vehicle was abandoned is unclear beyond the Dead Man’s Flats/Canmore area, and there is no publicly documented confirmed sighting of Marguerite between September 10 and the discovery of her car.
There is also no publicly identified person known to have travelled with her.
That leaves one particularly important question unanswered: do we actually know that Marguerite was the person who drove her vehicle to Dead Man’s Flats?
The publicly available information does not establish that she did.
It is entirely possible that she drove there herself, but without a confirmed sighting of Marguerite with the vehicle in the mountains, it cannot simply be assumed. Nor can it be established from the information available today whether she left the vehicle voluntarily, continued travelling with someone else, walked into the surrounding wilderness, or encountered something entirely unexpected.
The missing rifle creates another mystery. If Marguerite had it with her, where did it go? If she did not take it to the mountains, where had she left it? More than five decades later, there is no publicly documented recovery of either Marguerite or the firearm.
The unidentified man reportedly heard yelling outside her suite presents a different question. Was he connected to what happened, or was it simply an argument that took on greater significance only because Marguerite subsequently disappeared? Without knowing who he was or what the argument concerned, there is no responsible way to connect him to her disappearance.
Marguerite’s case therefore remains suspended between possibilities.
Perhaps she left Calgary intending to travel west and something happened after she reached the mountains. Perhaps the original investigators were correct to focus their attention on the wilderness surrounding the abandoned vehicle. Perhaps another person was involved somewhere between Calgary and Dead Man’s Flats. Or perhaps the location of the vehicle was only the beginning of a journey that continued somewhere else.
There simply isn’t enough surviving public evidence to know.
Marguerite was approximately five feet five inches tall and weighed around 126 pounds. She had a slender build, brown hair and blue eyes. One particularly distinctive identifying feature could still be important today: she had previously fractured her left ankle, which had been repaired with a two-inch screw. Records also associate her with the names Elizabeth Marguerite Peterson and Margaret Elizabeth Petersen.
More than 53 years have now passed since Marguerite disappeared. Her daughter grew up, searched for her, reconstructed pieces of her life, spoke with people who remembered her and even provided DNA in the hope that unidentified remains might finally bring an answer.
But Marguerite has never been found.
Her car was found near the mountains.
Her purse and possessions were left behind.
A rifle she had reportedly purchased was missing.
A large search produced nothing.
And decades later came the recollection of an unidentified man yelling outside her room shortly before she vanished.
Somewhere between Marguerite’s final days in Calgary and the discovery of that abandoned vehicle near Dead Man’s Flats, something happened that has remained hidden for more than half a century.
And perhaps the most haunting question is also the simplest.
Who drove Marguerite’s car into the mountains and where did she go from there?
If you have information on Marguerite’s case, please contact any of the following:
Canmore RCMP: 403-678-5519
Reference Case#: 20101321585
Canada’s Missing case reference: 2014004543
Crime Stoppers: 1-800-222-TIPS(8477)
Online at: https://www.canadiancrimestoppers.org/submit-a-tip/submit-a-tip
Crime Stoppers provides anonymous tipping
Send email to the National Centre for Missing Persons and Unidentified Remains at: canadasmissing-disparuscanada@rcmp-grc.gc.ca
Sources: Canada’s Missing, Shelley Sawatzky’s Missing from Dead Man’s Flats, biographical and case information associated with Shelley’s investigation, and Canada Unsolved’s compilation of the Marguerite Cardwell case.
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