more stats
2,178 ft
Distance
29 ft
Climb
-23 ft
Descent
00:04:55
Avg time
5 ft
Altitude change
177 ft
Altitude min
195 ft
Altitude max
177 ft
Altitude start
184 ft
Altitude end
0.2%
Grade
-10.4%
Grade max
8.3%
Grade min
850 ft
Distance climb
653 ft
Distance down
676 ft
Distance flat
00:04:55
Avg time

Inner Loop Details

  • Activities
    • Mountain Bike
    • Hike
    • Trail Running
    • Snowshoe
  • Riding Area
    Billerica State Forest
    Billerica, Massachusetts
  • Difficulty Rating
    Blue Rate
  • Voted Difficulty
    Black Diamond (2 votes)
  • Local Popularity
    75 in Mountain Biking [+]
    • 5 in Trail Running
    • 70 in Hiking
    • 5 in Snowshoeing
  • Global Ranking
    #3284 in Mountain Biking [+]
    • #92204 in Trail Running
    • #47372 in Hiking
    • #501 in Snowshoeing
  • Hiking SAC Scale
    T1 Hiking
  • Trail Type
    Singletrack
  • Direction
    Both Directions
  • Trail Visibility
    Always easy to follow
  • Dogs Allowed
    Yes
  • eBike Allowed
    No
  • Land Owner
    DCR

Fun, feature filled interior loop within the larger Northern Loop trail. Located at the bottom near the access road, starts as a short lollipop. Can be ridden either way. Blue trail with some black features. Initial monster rock not too difficult if scoped carefully.

Local Trail Association
Traditionally Indigenous Territory

Recent Activity on Trail

Past Week
  • 16 rides
  • 12 miles average
6 Months
  • 200 rides
  • 9 miles avg distance
All
  • 1,612 rides
  • Last: Sep 20, 2026
update trails status or condition

Inner Loop Trail Reports

statusdatedescription
May 12, 2026 @ 12:47pm (America/New_York)
May 12, 2026
Oct 18, 2025 @ 8:04am (America/New_York)
Oct 18, 2025
Jun 16, 2025 @ 9:38am
Jun 16, 2025
 Tree down across the trail. 10" diameter. Need chainsaw.
Jul 23, 2024 @ 7:32am
Jul 23, 2024
Jun 6, 2024 @ 6:58pm
Jun 6, 2024
more »
Status:
on May 12, 2026
Dry
Avg: 4.29 (4 votes)
Your vote: 0

view (8,755)
close
      Directions to inner-loop-154806 trailhead (42.573830, -71.298490)
      View on Discover Map

      Photos

      3 more »
      mtb
      170 |
      Nov 11, 2020 @ 4:51am
      Nov 11, 2020
      report
      mtb
      53 |
      Jun 16, 2025 @ 9:39am
      Jun 16, 2025
      report
      mtb
      38 |
      Jun 5, 2024 @ 2:04pm
      Jun 5, 2024

      Videos

      2 more »
      youtuber Fatbiking Russell Mill Pond and Billerica Town...
      mtb
      14:32 | 472 | Feb 10, 2021 , Billerica
      Northen Loop and Inside Loop
      mtb
      8:39 | 662 | Jun 27, 2020 , Billerica

      Technical Trail Features (TTF)

      Routes with this trail

      82
      Great Brook Farm Traverse Advanced Loop
      ★ 5.0 • 29 miles • 1,745 ft • 46 • Loop •
      A loop Featuring trails from Farm State Park, Russtle Mill State Forest, and Billrica trails.
      93
      Billerica State Forest 18 miler
      ★ 5.0 • 14 miles • 946 ft • 25 • Loop •
      Downloaded from NEMBA site.
      81
      2024 Great Brook Advanced Trifecta Route - PK Memorial
      ★ 2.5 • 30 miles • 1,840 ft • 57 • Loop •
      2024 NEMBA PK Memorial Advanced ride route. The route outside of will not be marked. Navigation is required.
      4.8 ★★★★★
      4 Ratings
      5 ★ 75%
      4 ★ 25%
      3 ★
      2 ★
      1 ★

      1 Review & Comments

      SiamDelightRules
      Some big rock features on this little trail - worth the detour when doing the rest of the loops in the area

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      Nearby Trails

      Billerica State Forest

      • By bigwheels87TF Pro & contributors
      • #154806 - 1,797 views

      Frequently Asked Questions

      ▼ Where is Inner Loop located?
      Inner Loop is located in Billerica State Forest, Billerica, Massachusetts, United States. It is part of the Billerica State Forest trail network. The trailhead is located at coordinates 42.57383, -71.29849.
      ▼ How hard is Inner Loop?
      Inner Loop is rated as Blue difficulty. The average grade is 0.2%.
      ▼ What is the elevation gain for Inner Loop?
      Inner Loop has 29 ft of elevation gain. The trail has 23 ft of elevation descent. The elevation ranges from 177 ft to 195 ft.
      ▼ Is Inner Loop a point to point trail?
      Inner Loop is not a point to point trail. The direction is Both Directions. The trail type is singletrack.
      ▼ How long is Inner Loop?
      Inner Loop is 2,178 ft long. The trail type is singletrack.
      ▼ Are dogs allowed on Inner Loop?
      Yes, dogs are allowed on Inner Loop. Please keep dogs on a leash where required and clean up after them.
      ▼ How do I access Inner Loop? Where is the closest parking trailhead?
      The closest parking and trailhead locations to Inner Loop are: View all parking locations in the area.
      ▼ How long does it take to ride Inner Loop?
      Based on recorded activities, it takes an average of 5 minutes to ride Inner Loop. The trail is 2,178 ft long. Actual times will vary based on fitness level, conditions, and pace. View recent activity logs for more details.
      ▼ How busy is Inner Loop?
      Inner Loop is a very popular trail. There have been 6,077 recorded activities on this trail. The trail has received 8,755 check-ins. View recent activity on this trail.

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