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Activity Recordings
Trailforks users anonymized public skilogs from the past 12 months.
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      Black Diamond Open Space (BDOS), a partnership between Evergreen Mountain Bike Alliance and King County Parks, is a centrally-located area consisting of a stacked loop network of new and existing trails connecting several popular mt biking trail systems together: Henry’s Ridge to the north, Summit Ridge (and Real Life Church) to the south and Lake Sawyer to the west.

      Differing from the techy and twisty trails of Henry, Sawyer, and Summit Ridge, the new trails at BDOS offer riders fun, flowy, and family-friendly rides on which to learn and progress. These trails were constructed with funding from a King County Community Partnership Grant, King County Youth Sports Facility Grant and a grant from REI.

      Through its partnership with King County Parks, Evergreen is currently maintaining the BDOS trails and working on a high level conceptual plan for future new trails in the BDOS area.

      Goals for future trails will be to provide the longest continuous climbs and descents in the entire BD/MV area, as well as to add skill-building trails and features like jumps, drops, and a pump track.

      With the new BDOS trails there are a variety of opportunities for all skill levels all in one area, which will only improve with the completion of Phase 2.
      Primary Trail Type: Cross-Country
      eBikes Allowed: No
      AKA: BDOS
      Land Status: City Managed
      Powerline Trailhead Parking google parking directions
      Access Info:
      Black Diamond Open Space parking lot is located on the east side of Highway 169, just south of Four Corners in Maple Valley.
      Activities Click to view
      Region Details
      • 3
      • 10
      • 9
      • 3

      Region Status
      Caution as of Jan 8, 2023
      Local Trail Association

      Stats

      Avg Trail Rating
      Trails (view details)
      25
      Trails Mountain Bike
      25
      Trails Hike
      18
      Trails Trail Running
      18
      Total Distance
      12 miles
      Total Descent
      1,346 ft
      Total Vertical
      160 ft
      Highest Trailhead
      706 ft
      Reports
      1,448
      Photos
      68
      Ridden Counter
      19,299

      Popular Black Diamond Open Space Mountain Biking Trails

      Photos of Black Diamond Open Space Mountain Bike

      143 |
      Jan 28, 2022 @ 12:22am
      Jan 28, 2022
      88 |
      Jan 28, 2022 @ 12:21am
      Jan 28, 2022
      trail: Sasquatch
      118 |
      May 22, 2021 @ 1:37pm
      May 22, 2021
      trail: Master Link
      51 |
      May 22, 2021 @ 1:37pm
      May 22, 2021
      trail: Master Link
      66 |
      May 22, 2021 @ 1:36pm
      May 22, 2021
      trail: Sasquatch
      97 |
      Mar 13, 2021 @ 10:50am
      Mar 13, 2021
      trail: Sasquatch
      103 |
      Mar 13, 2021 @ 10:50am
      Mar 13, 2021
      130 |
      Mar 13, 2021 @ 10:19am
      Mar 13, 2021

      Videos of Black Diamond Open Space Mountain Bike

      Tour of Kathleen with JJ
      trail: Kathleen
      2:07 | 295 | Mar 19, 2019
      Tour of Spooky with JJ
      trail: Spooky
      4:30 | 61 | Mar 6, 2019
      Golden Spike Edit
      trail: Spike
      0:55 | 281 | Oct 16, 2016
      G Spike
      trail: Spike
      3:22 | 359 | Jun 25, 2014
      Golden Spike trail
      trail: Spike
      1:22 | 108 | Feb 7, 2014
      Civic Dirt Jump Sesh
      trail: Broken Arm
      2:20 | 591 | Oct 9, 2011
      Duthie and Chuckanut Jumps...Really bored!
      trail: Broken Arm
      1:18 | 336 | Sep 30, 2011
      Short Ride
      trail: Broken Arm
      1:29 | 4005 | Jul 27, 2011

      Current Trail Warnings

      statustraildateconditionuserinfo
      Cheata
      Jan 14, 2023 @ 1:32am
      Jan 14, 2023
      Drypuch532

      Recent Trail Reports

      Activity Feed

      usernameactiontypetitledate
      user #1443075AwkragtvotetrailFresh Squeezed and 3 more
      Feb 3, 2023 @ 1:16pm
      2 days
      user #3359142NathanO27V02riddentrailRock & Roll and 8 more
      Jan 30, 2023 @ 12:48am
      Jan 30, 2023
      user #1443075AwkragtaddreportRemaster and 5 more
      Jan 28, 2023 @ 9:09pm
      Jan 28, 2023
      user #3364370trailfootwishlisttrailFresh Squeezed
      Jan 22, 2023 @ 6:21pm
      Jan 22, 2023
      user #3359128jasonlA3PiqriddentrailSasquatch and 2 more
      Jan 21, 2023 @ 7:25am
      Jan 21, 2023

      Recent Comments

      usernametypetitlecommentdate
      user #1868865silverramptrailBlind PigMeh, fading been into the woods
      Nov 12, 2022 @ 2:17pm
      Nov 12, 2022
      user #3218014lothi192trailKathleenStraightforward loop; very good for beginners...
      Oct 27, 2022 @ 6:27pm
      Oct 27, 2022
      user #2996933ConorVillarrealA9ntrailChilly BinSlightly overgrown near the end but passable
      Jul 9, 2022 @ 1:49pm
      Jul 9, 2022
      user #2465567AlspinstrailCrooshalRight at the end you start to get more speed...
      Jun 4, 2022 @ 4:14pm
      Jun 4, 2022
      user #1889584GsdrapertrailSuperchargerPunchy but short downhill. Uphill portion...
      Jun 1, 2022 @ 11:53am
      Jun 1, 2022

      Nearby Areas

      namedistance
      Summit Ridge 7 8 3 40.6 km
      Henry's Ridge Open Space 9 20 50.7 km
      Lake Sawyer 10 53 21.1 km
      Green River Gorge 14.1 km
      Kanaskat-Palmer State Park 12 15.2 km

      Local Badges


      Activity Type Stats

      activitytypetrailsdistancedescentdescent distancetotal verticalratingglobal rankstate rankphotosreportsroutesridelogs
      Mountain Bike2512 miles1,345 ft4 miles161 ft
      #292#139681,446212,073
      Hike1810 miles719 ft3 miles157 ft
      #429#2671,35945
      Trail Running1810 miles719 ft3 miles157 ft
      #430#2661,359145
      • By overdrive47 & contributors
      • Admins: BDTC
      • #9635 - 44,382 views
      • black diamond open space activity log | embed map of Black Diamond Open Space mountain bike trails | black diamond open space mountain biking points of interest

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