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- Mount McNamee - 13,780'
- September 16th, 2001 - Ryan Kowalski
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- Mount Maestas - 11,569'
- May 2, 1998 - Steve Fry
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- Maroon Peak (sometimes called South Maroon) - 14,156' -

- July 4, 1986, Alan Silverstein - CMC
- August 12, 1990 - Gary Stearns
- August 14, 1995 - Steve Parker
- June 13-15, 1998 - Los Alamos Mountaineers Club
- August 5, 1999 - Brian Schultz
- July 22-23, 2000 - Theron Welch
- June 30 - July4, 2000 - Jason Halladay
- July 22, 2000 - Steve Bremner
- August 15, 2000 - Brian Schultz
- August 18-20, 2000 - Los Alamos Mountaineers Club
- August 26, 2000 - Doug Cook
- June 24, 2001 - Paul Wilson
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- Maroon Peak, North
- See North Maroon Peak
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- Mt. Massive - 14,421' -

- August 1, 1983 - Gary Stearns
- August 25, 1994 - Bob Broeking - The White Spider
- September 5, 1994- Mark Vanderbrook
- July 8, 1995, Keith Jensen - CMC
- September 4, 1995 - Brian Rachford's Home Page
- July 13, 1997 - Brian Schultz
- July 26, 1997 - Dawn DuPriest
- July 26, 1997 - Nate Berg's Web Stop
- May 21, 1998 - Bill Neubert
- August 1, 1998 - Tom Stybr
- May 22, 1999 - Mike Kosel
- September 9, 1999 - Chris Palmer
- October 25, 1999 - Jim Mallory's Colorado Mountain Climbs
- June 23, 2001 - John Maki
- August 21, 2001 - Andrew White
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- Matterhorn Peak - 13,590'
- July 24, 1996 - Chris Wetherill
- July 21 - July 23, 2000 - Los Alamos Mountaineers Club
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- Mayflower Creek
- August 5, 1998 - Steve Fry
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- Mayflower Hill - 12,416'
- June 20, 2000 - Ryan Kowalski
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- McConnell Mountain
- June 19, 1999 - Dawn DuPriest
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- McHenrys
- August 26, 2000 - Bill Strand
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- Meadow Mountain - 11,632'
- June 6, 1999 - Dawn DuPriest
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- Medicine Bow Peak, WY - 12,013'
- July 1, 1994 - Brian Rachford's Home Page
- October 15, 1994 - Brian Rachford's Home Page
- March 10, 1995 - Brian Rachford's Home Page
- June 20, 1995 - Brian Rachford's Home Page
- April 6, 1996 - Brian Rachford's Home Page
- June 17, 1996 - Brian Rachford's Home Page
- May 9, 1997 - Brian Rachford's Home Page
- September 16, 2000 - Dawn DuPriest
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- Mount Meeker - 13,911' -
- August 21, 1998 - Los Alamos Mountaineers Club
- June 4, 1999 - Los Alamos Mountaineers Club
- January 15, 2000 - Steve Bremner
- June 22, 2001 - Kevin Craig
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- Midland Hill - 9,556'
- March 28, 1999 - Gary Swing
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- Milwaukee - 13,522'
- August 1984 - Chris Wetherill
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- Missouri Mountain - 14,067' -

- July 31, 1987 - Gary Stearns
- August 17, 1992- Mark Vanderbrook
- September 3, 1993 - Chris Wetherill
- June 25, 1994- Bob Broeking - The White Spider
- August 3, 1995 - Brian Rachford's Home Page
- September 13-14, 1997 - Los Alamos Mountaineers Club
- June 26, 1998 - Mike Kosel
- July 29, 1998 - Brian Schultz
- September 5-7, 1997 - Los Alamos Mountaineers Club
- September 19-20, 1998 - Dawn DuPriest
- July 10, 1999 - Steve Bremner
- August 21, 1999 - Jim Mallory's Colorado Mountain Climbs
- July 16, 2000 - Steve Bremner
- June 26, 2001 - Steve Bremner
- July 8, 2001 - John Maki
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- Moon Lake
- Summer 1995 - Dougs Hiking Adventures
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- Mormon Lakes
- July 4-5, 1997 - Steve Fry
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- Mosquito Peak - 13,781'
- December 31, 1994 - Bob Broeking - The White Spider
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- Mummy
- September 3, 2000 - Bill Strand