1,667 ft
-249 ft
Avg time


  • Activities
    • Hike
    • Snowshoe
    • Backcountry Ski
    Mountain Biking not recommended or allowed.
  • Riding Area
    Mount Greylock State Reservation
    Adams, Massachusetts
  • AKA
  • Difficulty Rating
  • Hiking SAC Scale
    T2 Mountain Hiking
  • Trail Type
  • Snow Grooming
  • Direction
    Both Directions
    Popular direction shown
  • Physical Rating
  • Trail Visibility
    Always easy to follow
  • Alpine Trail
  • Family Friendly
  • Dogs Allowed
  • Land Owner
    Mass DCR

This is the Appalachian Trail, which doubles as the upper part of the old Thunderbolt Run ski trail. It is also used as an uphill route, after those proceeding uphill have joined the trail from the uphill skin trail.

Please be aware of all uphill and downhill users.

Access Info

Uphill Users - please ascend on the far edge of the trail. The right side will at first be the best place to be, but soon thereafter you will want to switch to the left.

More Stats for Appalachian Trail - Mt Greylock, Upper Thunderbolt Run multi-use trail trail
  • Altitude change
    -249 ft
  • Altitude min
    3,113 ft
  • Altitude max
    3,362 ft
  • Altitude start
    3,362 ft
  • Altitude end
    3,114 ft
  • Grade
  • Grade max
  • Grade min
  • Distance down
    1,667 ft
  • Avg time
  • Avg reverse time
  • view trail stats
on Jan 1, 2023
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Trail Conditions
  • Unknown
  • Snow Groomed
  • Snow Packed
  • Snow Covered
  • Snow Cover Partial
  • Freeze/thaw Cycle
  • Icy
  • Prevalent Mud
  • Wet
  • Variable
  • Ideal
  • Dry
  • Very Dry
Trail Flow (Ridden Direction)
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The colour categories are based on what percentage of riders are riding a trail in its intended direction.
  • > 96%
  • > 90%
  • > 80%
  • > 70%
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  • < 50%
  • bi-directional trail
  • no data
Trail Last Ridden
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Trail Ridden Direction
The intended direction a trail should be ridden.
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  • Downhill Primary
  • Both Directions
  • Uphill Primary
  • Uphill Only
  • One Direction
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Trail Popularity ?
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Max Vehicle Width
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Radar Time
x Activity Recordings
Trailforks users anonymized public ridelogs from the past 6 months.
  • mountain biking recent
  • mountain biking (>6 month)
  • hiking (1 year)
  • moto (1 year)
Activity Recordings
Trailforks users anonymized public skilogs from the past 12 months.
  • Downhill Ski
  • Backcountry Ski
  • Nordic Ski
  • Snowmobile
Winter Trails
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      Directions to appalachian-trail-mt-greylock--upper-thunderbolt-run trailhead (42.638680, -73.164990)
      update trails status or condition

      Appalachian... Trail Reports

      Jan 1, 2023 @ 11:47pm
      Jan 1, 2023
      view all reports »

      Recent Ridelog Activity on Trail

      Past Week
      • 0 rides
      6 Months
      • 0 rides
      • 11 rides


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      Trail Lists

      Routes with this trail

      Appalachian National Scenic Trail - Complete2,075 miles
      Greylock Gould Loop6 miles

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      no videos have been added for Appalachian Trail - Mt Greylock, Upper Thunderbolt Run yet, add a video.
      • By mappermook TRAILFORKS WSF Trailforks & contributors
      • #411786 - 608 views

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