more stats
1,335 ft
Distance
8 ft
Climb
-124 ft
Descent
581 ft
High Point
-115 ft
Altitude change
455 ft
Altitude min
581 ft
Altitude start
466 ft
Altitude end
-8.7%
Grade
-43.1%
Grade max
7.2%
Grade min
253 ft
Distance climb
997 ft
Distance down
82 ft
Distance flat

F=ma Details

  • Activities
    • Mountain Bike
  • Riding Area
    Glenbervie Forest
    Whangarei
  • Difficulty Rating
    Blue Rate
  • Voted Difficulty
    Blue (1 vote)
  • Local Popularity
    80 in Mountain Biking
  • Trail Type
    Singletrack
  • Bike Type
    XC
  • Direction
    Downhill Only
    Popular Direction Shown
  • Climb Difficulty
    Blue
  • Physical Rating
    Moderate
  • Trail Visibility
    Always easy to follow
  • TTFs on Trail
    Bridge, Ladder Bridge
  • Year Opened
    2025
  • Land Owner
    Whangarei Mountain Bike Club

Predominantly downhill flowing singletrack, flat corners and fast straight sections but from the bridge at the bottom it's uphill to the end which links back into the very bottom of Douglas Drop.

Access Info

Starts on Firewood road just above the current entrance to Douglas drop and is in fact the old entrance to Douglas Drop which was closed due to a huge slip.

Trail Supporters
Local Trail Association
Traditionally Indigenous Territory

Recent Activity on Trail

Past Week
  • 0 rides
  •  
6 Months
  • 2 rides
  • 13 miles avg distance
All
  • 16 rides
  • Last: Jun 28, 2026
c1c2c3c4
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F=ma Trail Reports

statusdatedescription
Feb 27, 2026 @ 11:59am (Pacific/Auckland)
Feb 26, 2026
 Out in the clear cut the weeds are head height by the bridge and there's bush lawyer further along towards the end
Jan 7, 2026 @ 12:04pm (Pacific/Auckland)
Jan 6, 2026
 Looks like another amoeba has ridden a motorcross bike in here, track is torn up again [it's new damage]
Jan 1, 2026 @ 1:02pm (Pacific/Auckland)
Dec 31, 2025
 Motorbike damage
Dec 9, 2025 @ 1:53pm (Pacific/Auckland)
Dec 8, 2025
Nov 24, 2025 @ 11:49pm (Pacific/Auckland)
Nov 24, 2025
 Still too wet to ride responsibly, especially the bottom - once was enough.
more »
Status:
on Feb 27, 2026
Dry
Avg: 4.13 (1 votes)
Your vote: 0

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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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  • Downhill Only
  • Downhill Primary
  • Both Directions
  • Uphill Primary
  • Uphill Only
  • One Direction
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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 f-ma trailhead (-35.652680, 174.350490)

        Photos

        0 more »
        27 |
        Nov 10, 2025 @ 7:17pm
        Nov 10, 2025
        22 |
        Nov 6, 2025 @ 9:15pm
        Nov 6, 2025

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        Frequently Asked Questions About F=ma

        ▼ Where is F=ma located?
        F=ma is located in Glenbervie Forest, Whangarei, New Zealand. It is part of the Glenbervie Forest trail network. The trailhead is located at coordinates -35.65268, 174.35049.
        ▼ How hard is F=ma?
        F=ma is rated as Blue difficulty. The physical rating is Moderate. The average grade is 8.7%. The climb difficulty is rated Blue.
        ▼ What is the elevation gain for F=ma?
        F=ma has 8 ft of elevation gain. The trail has 124 ft of elevation descent. The elevation ranges from 455 ft to 581 ft.
        ▼ Is F=ma a point to point trail?
        Yes, F=ma is a point to point trail. The direction is Downhill Only. The trail type is singletrack.

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