more stats
3,556 ft
Distance
38 ft
Climb
-77 ft
Descent
00:05:55
Avg time
-40 ft
Altitude change
879 ft
Altitude min
921 ft
Altitude max
919 ft
Altitude start
879 ft
Altitude end
-1.1%
Grade
-11.5%
Grade max
11.5%
Grade min
797 ft
Distance climb
1,611 ft
Distance down
1,056 ft
Distance flat
00:05:55
Avg time

Grand Chasm Details

  • Activities
    • Mountain Bike
    • Winter Fat Bike
    • Hike
    • Trail Running
    • Snowshoe
  • Riding Area
    Trowbridge Forest
    Thunder Bay, Ontario
  • Difficulty Rating
  • Voted Difficulty
    Blue (1 vote)
  • Local Popularity
    95 in Mountain Biking heatmap [+]
    • 60 in Trail Running
    • 85 in Hiking
    • 5 in Snowshoeing
    • 100 in Winter Fat Biking
  • Global Ranking
    #25490 in Mountain Biking [+]
    • #137800 in Trail Running
    • #111568 in Hiking
    • #16050 in Snowshoeing
    • #49 in Winter Fat Biking
  • Provincial Ranking
    #665 in Mountain Biking · Ontario [+]
    • #4,037 in Trail Running
    • #3,851 in Hiking
    • #2,602 in Snowshoeing
    • #10 in Winter Fat Biking
  • Hiking SAC Scale
    T1 Hiking
  • Trail Type
    Singletrack
  • Bike Type
    AM, XC, Fat
  • Direction
    Downhill Primary
    Popular Direction Shown
  • Climb Difficulty
    Blue
  • Physical Rating
    Moderate
  • Season
    May-Oct
  • Dogs Allowed
    Yes
  • TTFs on Trail
    Berm, Bridge, Drop, Jump, Ladder Bridge, Rock Face
  • Ride in Rain
    Yes

Originally built in the the mid 90's the area around Grand Chasm has seen significant changes over the years and multiple lines developed as local riders looked to take advantage of the terrain and natural features around the heart of the old mines.

In 2011 the local mountain bike club, in consultation with IMBA representatives, started to redevelop and align the trails in order to improve flow, length and sustainability of the trail. After nearly 4 years of work the final produce was unveiled and a new 1.1km signature trail was opened in Shuniah Mines. Riders are now treated to a true flow trail with long sweeping sections, bermed corners, and plenty of optional tech features including; a ladder bridge, roll-able jumps and rock features. The new trail takes advantage of modern trail building techniques, while still maintaining the "old school" feel.

*New for 2016*
Due to the closures of old mine shafts in the area by the city of Thunder Bay, the top portion of Grand Chasm has required significant re-routing. Local builders with the support of the city have been given the opportunity to complete the first machine built section of trail in Shuniah Mines. Expected to open when work is completed in the spring of 2016, the new top portion of the trail will contain some of the largest XC features every constructed in the trail system.

Trail Supporters

Local Trail Association

Recent Activity on Trail

Past Week
  • 4 rides
  • 7 miles average
6 Months
  • 334 rides
  • 12 miles avg distance
All
  • 1,789 rides
  • Last: Aug 16, 2026
c1c2c3c4
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February
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update trails status or condition

Grand Chasm Trail Reports

statusdatedescription
May 15, 2026 @ 9:46am (America/Toronto)
May 15, 2026
All trees cleared off Grand Chasm.
May 10, 2026 @ 4:38pm (America/Toronto)
May 10, 2026
Tree down
May 10, 2025 @ 2:44pm
May 10, 2025
reporter Trails are in good shape. There is some winter debris on some trails so ride with care. Please ride through any puddles.
Apr 26, 2025 @ 1:57pm
Apr 26, 2025
reporter The spring thaw is in full effect. Please avoid the trails
May 20, 2024 @ 5:31am
May 20, 2024
more »
Status:
on May 15, 2026
Ideal
Avg: 4.45 (16 votes)
Your vote: 0

view (9,533)
close
      Directions to grand-chasm trailhead (48.476760, -89.206510)

      Photos

      31 more »
      mtb
      126 |
      Sep 12, 2022 @ 11:01am
      Sep 12, 2022
      mtb
      102 |
      Sep 12, 2022 @ 11:01am
      Sep 12, 2022
      mtb
      176 |
      Aug 22, 2021 @ 7:52pm
      Aug 22, 2021
      mtb
      197 |
      Aug 22, 2021 @ 7:52pm
      Aug 22, 2021

      Videos

      4 more »
      Shuniah Mines Pretzel Trail
      mtb
      1966 | Nov 6, 2014 , Thunder Bay
      Scott vs Rock
      mtb
      0:09 | 424 | Aug 18, 2021 , Thunder Bay
      Scott vs the rock
      mtb
      0:09 | | Aug 17, 2021 , Thunder Bay
      Fall-time in Shuniah
      mtb
      0:59 | 355 | Nov 2, 2018 , Thunder Bay

      Routes with this trail

      more »
      13 miles • 902 ft • 22 • Loop • Race •
      The Shuniah Forty Miner returns for 2026 with distances for everyone. 1 Lap - 20 km 2 Laps - 40 km 3 Laps...
      11 miles • 857 ft • 26 • Loop • Race •
      Everyone's favourite race course Hover your mouse across the elevation profile to follow the green dot...
      8 miles • 730 ft • 16 • Loop • Race •
      Everyone's favourite race course! Hover your mouse across the elevation profile to follow the green dot...
      4.7 ★★★★★
      16 Ratings
      5 ★ 69%
      4 ★ 25%
      3 ★ 6%
      2 ★
      1 ★

      Reviews / Comments

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      • By WanderingManTF Pro BSMTB & contributors
      • #18215 - 7,612 views

      Frequently Asked Questions

      ▼ Where is Grand Chasm located?
      Grand Chasm is located in Trowbridge Forest, Thunder Bay, Ontario, Canada. It is part of the Trowbridge Forest trail network. The trailhead is located at coordinates 48.47676, -89.20651.
      ▼ How hard is Grand Chasm?
      Grand Chasm is rated as Blue difficulty. The physical rating is Moderate. The average grade is 1.1%. The climb difficulty is rated Blue.
      ▼ What is the elevation gain for Grand Chasm?
      Grand Chasm has 38 ft of elevation gain. The trail has 77 ft of elevation descent. The elevation ranges from 879 ft to 921 ft.
      ▼ Is Grand Chasm a point to point trail?
      Grand Chasm is not a point to point trail. The direction is Downhill Primary. The trail type is singletrack.
      ▼ How long is Grand Chasm?
      Grand Chasm is 3,556 ft long. The trail type is singletrack.
      ▼ Are dogs allowed on Grand Chasm?
      Yes, dogs are allowed on Grand Chasm. Please keep dogs on a leash where required and clean up after them.
      ▼ When is the best time of year to ride Grand Chasm?
      Based on activity log data, the most popular months to ride Grand Chasm are:
      • August (168 activities)
      • July (156 activities)
      • September (131 activities)
      Check the reports page for current trail conditions.
      ▼ How do I access Grand Chasm? Where is the closest parking trailhead?
      The closest parking and trailhead locations to Grand Chasm are: View all parking locations in the area.
      ▼ How long does it take to ride Grand Chasm?
      Based on recorded activities, it takes an average of 6 minutes to ride Grand Chasm. The trail is 3,556 ft long. Actual times will vary based on fitness level, conditions, and pace. View recent activity logs for more details.
      ▼ How busy is Grand Chasm?
      Grand Chasm is a very popular trail. There have been 8,449 recorded activities on this trail. The trail has received 9,533 check-ins. View recent activity on this trail.

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