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Trail Conditions
  • Unknown
  • Snow Groomed
  • Snow Packed
  • Snow Covered
  • Snow Cover Inadequate
  • Freeze/thaw Cycle
  • Icy
  • Prevalent Mud
  • Wet
  • Variable
  • Ideal
  • Dry
  • Very Dry
Trail Flow (Ridden Direction)
Trailforks scans users ridelogs to determine the most popular direction each trail is ridden. A good flowing trail network will have most trails flowing in a single direction according to their intension.
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
Trailforks scans ridelogs to determine the last time a trail was ridden.
  • < 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.
  • most popular
  • popular
  • less popular
  • not popular
ATV/ORV/OHV Filter
Max Vehicle Width
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Radar Time
x Activity Recordings
Trailforks users anonymized public ridelogs from the past 6 months.
  • mountain biking recent
  • mountain biking (>6 month)
  • hiking (1 year)
  • moto (1 year)
Activity Recordings
Trailforks users anonymized public skilogs from the past 12 months.
  • Downhill Ski
  • Backcountry Ski
  • Nordic Ski
Jump Magnitude Heatmap
Heatmap of where riders jump on trails. Zoom in to see individual jumps, click circles to view jump details.
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      East Bay Regional Park
      Primary Trail Type: All-Mountain & Downhill
      Land Status: Regional Recreation Area
      Activities Click to view
      Region Details
      • 2
      • 2

      Region Status
      Caution as of Aug 27, 2022

      Stats

      Avg Trail Rating
      Trails (view details)
      4
      Trails Mountain Bike
      4
      Trails Hike
      4
      Trails Trail Running
      4
      Total Distance
      12 miles
      Total Descent
      3,273 ft
      Total Vertical
      1,014 ft
      Highest Trailhead
      1,277 ft
      Reports
      23
      Photos
      13
      Ridden Counter
      240

      Popular Black Diamond Mines Regional Preserve Trails

      Recent Ride Log Activity in Region

      Today
      • 0 rides
      Yesterday
      • 1 rides
      Past Week
      • 12 rides

      Photos of Black Diamond Mines Regional Preserve Mountain Bike

      19 |
      May 6, 2022 @ 2:12pm
      May 6, 2022
      37 |
      Dec 10, 2021 @ 12:51pm
      Dec 10, 2021
      75 |
      Nov 25, 2020 @ 11:49am
      Nov 25, 2020
      54 |
      Oct 6, 2020 @ 9:11pm
      Oct 6, 2020
      66 |
      Oct 6, 2020 @ 9:11pm
      Oct 6, 2020
      57 |
      Oct 6, 2020 @ 9:11pm
      Oct 6, 2020
      44 |
      Aug 16, 2020 @ 1:28pm
      Aug 16, 2020
      42 |
      May 30, 2020 @ 2:04pm
      May 30, 2020

      Videos of Black Diamond Mines Regional Preserve Mountain Bike

      Contra Loma Trail
      122 | Sep 2, 2020 , Antioch
      youtuber Trail Tourist Ep11 : 420 Black Diamond Mines...
      8:13 | 504 | Apr 23, 2020 , Antioch
      youtuber Trail Tourist Ep11 : 420 Black Diamond Mines...
      8:13 | 334 | Apr 23, 2020 , Antioch

      Recent Trail Reports

      Activity Feed

      usernameactiontypetitledate
      user #2891319Michelecju9KDwishlistregionBlack Diamond Mines Regional Preserve
      Sep 2, 2022 @ 9:53pm
      Sep 2, 2022
      user #2041907KrustaddreportAcorn Trail
      Aug 27, 2022 @ 9:32pm
      Aug 27, 2022
      user #2041907KrustaddreportContra Loma Trail
      Aug 19, 2022 @ 9:17pm
      Aug 19, 2022
      user #2879062Jjside1addphoto in My City
      May 6, 2022 @ 2:12pm
      May 6, 2022
      user #160333moneytimetycoonaddreportHomestead Trail Connector and 1 more
      Feb 28, 2022 @ 8:24pm
      Feb 28, 2022

      Activity Type Stats

      activitytypetrailsdistancedescentdescent distancetotal verticalratingglobal rankstate rankphotosreportsroutesridelogs
      Mountain Bike412 miles3,274 ft7 miles1,014 ft
      #8,472#3,55713231417
      Hike412 miles3,274 ft7 miles1,014 ft
      #7,491#3,4012329
      Trail Running412 miles3,274 ft7 miles1,014 ft
      #7,472#3,389237
      • By DiabloDave & contributors
      • Admins: BTCEB, bkxc
      • #26518 - 1,989 views
      • black diamond mines regional preserve activity log | embed map of Black Diamond Mines Regional Preserve mountain bike trails |

      Downloading of trail gps tracks in kml & gpx formats is enabled for Black Diamond Mines Regional Preserve.
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