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SaveBlack 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.
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.
source: Evergreen MTB Alliance: BDOS
Primary Trail Type: Cross-Country
eBikes Allowed:
No
AKA: BDOS
Land Status: City Managed
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
- Mountain Bike
35 trails
- Hike
27 trails
- Trail Running
27 trails
Region Details
- 3
- 13
- 10
- 2
Region Status
Open as of Jun 26, 2026Local Trail Association
Stats
- Avg Trail Rating
- Trails (view details)
- 28
- Trails Mountain Bike
- 41
- Trails Hike
- 27
- Trails Trail Running
- 27
- Total Distance
- 12 miles
- Total Descent
- 1,346 ft
- Total Vertical
- 160 ft
- Highest Trailhead
- 706 ft
- Reports
- 1,699
- Photos
- 78
- Ridden Counter
- 27,455
Popular Black Diamond Open Space Mountain Biking Trails
• 90 ★ 3.9 • 2,208 ft • 66 ft • 1,760 •
Easygoing, machine-built beginner loop. Fast and flowy for the most part with an abundance of berms and rollers to pump your way through. This is a great first trail to take beginners on, and in turn, very kid-friendly as well. Also...
• 100 ★ 3.7 • 1,640 ft • 8 ft • 1,742 •
Mix of an old primitive trail ( ) and new machine built flow ( ). A few of the old sections have been reworked to drain and flow better, while a few of the original sections remain untouched, or remain as side options to the new...
• 95 ★ 3.9 • 4,183 ft • 124 ft • 1,736 •
Flowy climb and descent. Crank your way to the top whilst carving and pumping your way though an abundance of berms and rollers, and then rip back down through a fast descent with small tables, whoops, mid sized gaps, and even a short,...
• 100 ★ 4.3 • 1,778 ft • 0 ft • 1,644 •
Fast and flowy descent that features tabletop jumps, rollers that can be jumped as doubles, small whoops, and a huge berm to rail right at the start.
• 100 ★ 2.5 • 446 ft • 0 ft • 1,563 •
Connects the start of the descent with the top of and the loop.
• 95 ★ 3.5 • 1,946 ft • 18 ft • 1,512 •
Flowy, rolling, machine-built trail with berms, rollers, a mellow rock garden, and even a tabletop jump just before it should you have the speed.
• 90 ★ 3.8 • 915 ft • 14 ft • 1,251 •
Flowy, machine-built trail with plenty of berms and rollers.
Black Diamond Open Space Mountain Bike Routes
11 miles • 667 ft • 12 • Loop •
Fun route for groups with varied rider skill & fitness, and a good look at what's available while...
6 miles • 484 ft • 11 • Out & Back •
A planned route of some of the fun things at Black Diamond/Henry's. Without focusing on the popular...
10 miles • 309 ft • 10 •
trail route test for my second ride at this spot that's similar to soaring eagle but much more trails and...
12 miles • 437 ft • 15 •
Highway parking lot to Upper. Easy to moderate trails.
• 15 miles • 138 ft • 2 •
• 20 miles • 831 ft • 8 •
Photos of Black Diamond Open Space Mountain Bike
Videos of Black Diamond Open Space Mountain Bike
trail: Kathleen
2:07 |
371 |
Mar 19, 2019
trail: Spooky
4:30 |
77 |
Mar 6, 2019
trail: Spike
0:55 |
303 |
Oct 16, 2016
trail: Supercharger
4:06 |
76 |
Feb 16, 2025 , Maple Valley
trail: Crooshal
3:41 |
151 |
Feb 9, 2025 , Maple Valley
trail: Broken Arm
2:20 |
604 |
Oct 9, 2011
trail: Broken Arm
0:18 |
341 |
Sep 30, 2011
trail: Broken Arm
0:29 |
4028 |
Jul 27, 2011
Recent Trail Reports
| status | trail | date | condition | info | user |
|---|---|---|---|---|---|
| Little Something Special | Jun 26, 2026 @ 3:48pm (America/Los_Angeles) Jun 26, 2026 | Ideal | lloigor | ||
| Crooshal | Jun 11, 2026 @ 5:37pm (America/Vancouver) Jun 11, 2026 | Ideal | Awkragt | ||
| Supercharger | Jun 11, 2026 @ 5:37pm (America/Vancouver) Jun 11, 2026 | Ideal | Awkragt | ||
| Fresh Squeezed | Jun 11, 2026 @ 5:37pm (America/Vancouver) Jun 11, 2026 | Ideal | Awkragt | ||
| Brain Bucket | Jun 11, 2026 @ 5:37pm (America/Vancouver) Jun 11, 2026 | Ideal | Awkragt | ||
| Remaster | Jun 11, 2026 @ 5:37pm (America/Vancouver) Jun 11, 2026 | Ideal | Awkragt | ||
| Remasterd | Jun 11, 2026 @ 5:37pm (America/Vancouver) Jun 11, 2026 | Ideal | Awkragt | ||
| Kathleen | Jun 11, 2026 @ 12:00pm (America/Los_Angeles) Jun 11, 2026 | Unknown | StumpyPirate | ||
| Sasquatch | Jun 2, 2026 @ 10:25pm (America/Los_Angeles) Jun 2, 2026 | Variable | Jburris | ||
| Brain Wave | Jun 2, 2026 @ 10:21pm (America/Los_Angeles) Jun 2, 2026 | Ideal | Jburris |
Activity Feed
| username | action | type | title | date |
|---|---|---|---|---|
| PavloX84OBi | wishlist | route | activity #99634958 | Jul 20, 2026 @ 2:50pm 2 hours |
| Anselp7FbbQ | wishlist | trail | activity #99621899 | Jul 20, 2026 @ 11:14am 6 hours |
| IG7JA2A7 | wishlist | region | activity #98885310 | Jul 10, 2026 @ 3:28pm Jul 10, 2026 |
| nIcFr | wishlist | region | activity #98178904 | Jun 30, 2026 @ 9:52pm Jun 30, 2026 |
| lloigor | add | report | activity #97861953 | Jun 26, 2026 @ 3:51pm Jun 26, 2026 |
Recent Comments
| username | type | title | comment | date |
|---|---|---|---|---|
| report | Concur - no snow cover on trail. Full access... | Mar 16, 2026 @ 3:21pm Mar 16, 2026 | ||
| trail | This trail was more engaging before the... | May 1, 2025 @ 1:58pm May 1, 2025 | ||
| report | O l l lom m ill | Feb 28, 2025 @ 5:15pm Feb 28, 2025 | ||
| trail | @denidil - I feel her pain. I'm very much a... | Sep 30, 2024 @ 2:50pm Sep 30, 2024 | ||
| trail | The steepest climb of all the trails in BDOS.... | Sep 23, 2024 @ 4:13pm Sep 23, 2024 |
Nearby Areas
| name | distance | ||||
|---|---|---|---|---|---|
| Summit Ridge | 7 | 5 | 3 | 4 | 0.6 km |
| Henry's Ridge Open Space | 12 | 22 | 4 | 0.7 km | |
| Lake Sawyer | 9 | 47 | 2 | 1.1 km | |
| Legacy Park | 16 | 2.2 km | |||
| Cedar Creek Park | 4 | 6 | 3.5 km |
Local Badges
-
Completionist26 awarded
Local Products
Activity Type Stats
| activitytype | trails | distance | descent | descent distance | total vertical | rating | global rank | state rank | photos | reports | routes | ridelogs |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Mountain Bike | 35 | 12 miles | 1,345 ft | 4 miles | 161 ft | #768 | #297 | 84 | 1,716 | 4 | 19,533 | |
| Hike | 27 | 10 miles | 719 ft | 3 miles | 157 ft | #9,440 | #3,623 | 1,603 | 105 | |||
| Trail Running | 27 | 10 miles | 719 ft | 3 miles | 157 ft | #8,475 | #2,975 | 1,603 | 250 |
Frequently Asked Questions About Black Diamond Open Space
▼
What are the highest rated mountain biking trails in Black Diamond Open Space?
▼
What is the best time of the year to ride in Black Diamond Open Space?
Based on ride log data, the most popular months to ride in Black Diamond Open Space are:
- July (620 activities)
- August (447 activities)
- May (396 activities)
▼
Where can I park to ride in Black Diamond Open Space?
There are 2 parking locations listed in Black Diamond Open Space. The most popular parking spots are:
▼
What is the longest trail in Black Diamond Open Space?
The longest trail in Black Diamond Open Space is Sasquatch at 1.7 miles. View all trails sorted by distance.
Activities
Trails
- Hard trails in Black Diamond Open Space
- Easy trails in Black Diamond Open Space
- Favorite trails in Black Diamond Open Space
- Most ridden trails in Black Diamond Open Space
- Singletrack in Black Diamond Open Space
- Viewpoint trails in Black Diamond Open Space
- Trails with technical features in Black Diamond Open Space
- Race routes in Black Diamond Open Space
Points of Interest
- By overdrive47 & contributors
- Admins: EMBA-C2S
- #9635 - 71,511 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
Downloading of trail gps tracks in kml & gpx formats is enabled for Black Diamond Open Space.
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