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Mark Bonner Missing Person Case

Last seen in Boulder, Colorado on Mar 20, 1978

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Case Description

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In the quiet town of Boulder, Colorado, a young man named Mark Allen Bonner seemingly vanished without a trace, leaving behind a mystery that has endured for decades. On March 20, 1978, the 23-year-old was last seen, and the circumstances surrounding his disappearance have remained frustratingly vague. At the time, Bonner was house-sitting at a residence on Neva Road, located north of Boulder. Details about his last known movements are scarce, with no witnesses to his departure or any indication ...Read More
Last Seen: Mar 20, 1978

Links to Additional Sources (7)

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  • Mark Bonner - The Charley Project
  • Mark Allen Bonner- A Cold Missing Persons Case in Colorado - Reddit
    •     ...View 5 additional sources

    Victim Details

    Aug 05, 2014

    Jul 26, 2022

    Mark

    Bonner

    70

    23

    75 inches

    150 lbs

    White / Caucasian

    Male

    Mar 20, 1978

    Boulder

    Colorado

    Boulder County

    23406

    Boulder County Sheriff's Office

    Boulder

    Colorado

    Boulder County

    80301

    Steven Ainsworth

    Detective

    5600 Flatiron Parkway, Colorado

    3034413600

    County

    Law Enforcement

    https://www.bouldercounty.org/safety/sheriff/

    78-3741

    Boulder County Sheriff's Office

    Blond/Strawberry

    Blue

    Blue

    05/28/2026


    Area Last Seen:

    Forum Posts (2)

    Does anyone have information on Mark Bonner’s family or friends at the time he disappeared? I've b... ...Read More
    12/17/2024
    Does anyone have any info on the sighting of Mark Bonner by the older man who reportedly saw him on ... ...Read More
    04/10/2024

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