more stats
2.3 miles
Distance
110 ft
Climb
-107 ft
Descent
00:16:58
Avg time
3 ft
Altitude change
709 ft
Altitude min
763 ft
Altitude max
718 ft
Altitude start
722 ft
Altitude end
-11.5%
Grade max
11.1%
Grade min
2,900 ft
Distance climb
3,602 ft
Distance down
1 mile
Distance flat
00:16:58
Avg time

Underground Loop Details

  • Activities
    • Mountain Bike
    • Hike
    • Trail Running
  • Riding Area
    The Underground
    Grand Rapids, Michigan
  • Difficulty Rating
    Blue Rate
  • Local Popularity
    100 in Mountain Biking [+]
    • 70 in Trail Running
    • 95 in Hiking
  • Trail Type
    Singletrack
  • Bike Type
    XC, DJ
  • Direction
    One Direction
  • Climb Difficulty
    Green
  • Physical Rating
    Moderate
  • Trail Visibility
    Always easy to follow
  • Dogs Allowed
    Yes
  • TTFs on Trail
    Berm, Drop, Jump, Gap Jump
  • Land Owner
    City of Grand Rapids

No community description for Underground Loop trail has been added yet!

AI Generated Description

Underground Loop is a 2 mile popular blue difficulty singletrack trail located near Grand Rapids Michigan. This mountain bike primary trail can be used one direction and has a moderate overall physical rating with a 110 ft green climb. It features berm, drop, jump and gap jump. Trail visibility is always easy to follow. On average it takes 16 minutes to complete this trail.

Disclaimer

Current Map is not up to date

Local Trail Association
Traditionally Indigenous Territory

Recent Activity on Trail

Past Week
  • 1 rides
  • 6 miles average
6 Months
  • 15 rides
  • 8 miles avg distance
All
  • 121 rides
  • Last: Jun 9, 2026
c1c2c3c4
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Status:
on May 29, 2026
Dry
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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%
  • > 50%
  • < 50%
  • bi-directional trail
  • no data
Trail Last Ridden
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  • < 2 days
  • < 1 week
  • < 2 weeks
  • < 1 month
  • < 6 months
  • > 6 months
Trail Ridden Direction
The intended direction a trail should be ridden.
  • Downhill Only
  • Downhill Primary
  • Both Directions
  • Uphill Primary
  • Uphill Only
  • One Direction
Contribute Details
Colors indicate trail is missing specified detail.
  • Description
  • Photos
  • Description & Photos
  • Videos
Trail Popularity ?
Trailforks scans ridelogs to determine which trails are ridden the most in the last 9 months. Trails are compared with nearby trails in the same city region with a possible 25 colour shades. Think of this as a heatmap, more rides = more kinetic energy = warmer colors.
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Max Vehicle Width
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Trails are colored based on popularity. The more popular a trail is, the more red. Less popular trails trend towards green.
Jump Magnitude Heatmap
Heatmap of where riders jump on trails. Zoom in to see individual jumps, click circles to view jump details.
BC Backroad Status

Service Road Atlas is a free to use, community-driven service for viewing and creating reports on the numerous back-country service roads around B.C. and Alberta.

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Slope Aspect
Direction the slope faces
Flat N NE E SE S SW W NW
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        Directions to underground-loop trailhead (42.921820, -85.633170)

        Photos

        27 more »
        668 |
        Apr 30, 2020 @ 7:34pm
        Apr 30, 2020
        839 |
        Feb 29, 2004 @ 7:43pm
        Feb 29, 2004
        181 |
        May 29, 2024 @ 6:49am
        May 29, 2024
        175 |
        Mar 24, 2024 @ 5:09pm
        Mar 24, 2024

        Videos

        4 more »
        youtuber Post Crash Anxiety & Just Sending It at...
        20:05 | 464 | May 11, 2021 , Grand Rapids
        Underground starts a little after 5 minutes
        10:10 | 316 | Jul 8, 2021 , Grand Rapids
        youtuber Post Crash Anxiety & Just Sending It at...
        20:05 | 623 | May 21, 2021 , Grand Rapids
        Underground jump lines
        0:50 | 82 | Jul 9, 2024 , Grand Rapids

        Routes with this trail

        57
        EGR Trifecta Tour (Tue/Thu/Sat)
        21 miles • 858 ft • 11 • Loop •
        A relatively easy route linking Fred Bunn Trails @ Manhattan Park (EGR), The Underground (GR), and...

        Trail Events

        (1) past events on this trail

        1 Review & Comments


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        Nearby Trails

        The Underground

        Frequently Asked Questions About Underground Loop

        ▼ Where is Underground Loop located?
        Underground Loop is located in The Underground, Grand Rapids, Michigan, United States. It is part of the The Underground trail network. The trailhead is located at coordinates 42.92182, -85.63317.
        ▼ How hard is Underground Loop?
        Underground Loop is rated as Blue difficulty. The physical rating is Moderate. The climb difficulty is rated Green.
        ▼ What is the elevation gain for Underground Loop?
        Underground Loop has 110 ft of elevation gain. The trail has 107 ft of elevation descent. The elevation ranges from 709 ft to 763 ft.
        ▼ Is Underground Loop a point to point trail?
        Yes, Underground Loop is a point to point trail. The direction is One Direction. The trail type is singletrack.

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