20.3 miles
2,692 ft
-2,696 ft
1,435 ft
High Point

Turning Bill's descent in to a 20 miler

Detailed Description
Bill's Extended Loop is a 20 mile moderately popular easy route located near Woodacre California. This mountain bike only route. This route includes 3 trails. This route climbs 2,692 ft with a max elevation of 1,435 ft then descends -2,696 ft.
Local Trail Association
Please consider joining or donating to the local riding association to support trail development & maintenance.

Trail Products

12 Reviews & Comments

  • + 0
Redrob650 (Oct 15, 2022 at 17:34)
Trail Bill's Trail
There are sawed logs every quarter mile or so that you have to zig zag. One is around a blind turn and extremely dangerous. It almost launched me off the hillside. I had to skid out last minute and slammed my gears into the side of it. This trail is pretty boring in general so won’t be riding it again.
  • + 0
Jefferberg8 (Jul 8, 2022 at 19:44)
Trail Bill's Trail
The fallen tree was still down but manageable to get by without any issues. A little overgrown with poison oak in some spots but otherwise in good condition.

I did as an out-and-back. Good climbing and a long flowy decent, fun with some speed but nothing technical to deal with.
  • + 0
hellomihai (Feb 13, 2022 at 10:38)
Trail Bill's Trail
Good ride. Only one fallen tree blocking the path but can be crossed with a little effort.
  • + 0
MtbSince84 (Dec 20, 2020 at 21:26)
Trail Bill's Trail
Closed for the rainy season as of this weekend. Locked gates at both ends of trail.
  • + 1
Millerwill (Dec 14, 2020 at 19:28)
Trail Bill's Trail
Bill's Trail is CLOSED UNTIL APRIL 2021. Effective 12.14.20
  • + 1
tofudog (Oct 13, 2020 at 13:22)
Trail Bill's Trail
Concur that this trail is fantastic and meticulously maintained. Nice, easy going grade, well-shaded. Despite the fire road leading to the trail head being super dry and loose, Bill's Trail is just moist enough to provide excellent traction.
  • + 0
mchoffmann (Aug 5, 2020 at 10:29)
Trail Bill's Trail
This is a super nice trail in perfect condition. Thanks to everyone who made this happen. I would recommend doing this trail uphill since it is nicely shaded almost all the way and not steep. Perfectly doable on a gravel bike as well.
  • + 0
Tonymosa (May 20, 2020 at 21:51)
Trail Bill's Trail
Double bonus points to all that made this happen!
  • + 0
Macman87 (May 3, 2020 at 0:59)
Trail Bill's Trail
Is it better to ride up or down Bill’s Trail?
  • + 1
MtbSince84 (Dec 7, 2020 at 8:35)
Trail Bill's Trail
I rode both up and down it yesterday. It was great in both directions: gradual grade, smooth surface. I have not ridden the alternative, Barnabe Fire Road, but its description calls it "primarily downhill", so I'm assuming it has some (typical for Marin) very steep grades. So: consider riding both up and down on Bill's trail, or if you want to ride down a different way than you rode up, try riding up Bill's and down Barnabe Fire.
  • + 1
Bro-tato (Apr 25, 2020 at 16:49)
Trail Bill's Trail
Bill’s Trail is fully open to bikes now! And all fallen trees have been removed
  • + 1
Chipmsmith (May 4, 2017 at 13:36)
Trail Bill's Trail
Bills trail is closed from Fallon trees that are uncrossable even on foot. It is way overgrown and covered in poison oak. Don't ride or hike it!

Trails in Route


  • Riding area
  • Primary Activity
    Mountain Bike
  • Difficulty rating
  • Ridelogs
More Stats for Bill's Extended Loop mountain bike route
  • Altitude change
    -4 ft
  • Altitude min
    107 ft
  • Altitude start
    399 ft
  • Altitude end
    394 ft
  • Grade max
  • Grade min
  • Distance climb
    10 miles
  • Distance down
    8 miles
  • Distance flat
    2 miles
no votes yet
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
Max Vehicle Width

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
  • Snowmobile
Jump Magnitude Heatmap
Heatmap of where riders jump on trails. Zoom in to see individual jumps, click circles to view jump details.
Trails Deemphasized
Trails are shown in grey.
Only show trails with NO bikes.

Save the current map location and zoom level as your default home location whenever this page is loaded.

Trail transparency

Recent Trail Reports Along Route

Bill's Trail
Dec 27, 2022 @ 11:37am
Dec 27, 2022
Devil's Gulch Fire Road
Jan 30, 2022 @ 2:18pm
Jan 30, 2022
The trail cuts through Devil’s Gulch Farms for a tiny stretch, and sometimes the gates are locked, and the owner’s not happy to have visitors…
French Ranch Fire Road
Oct 31, 2021 @ 10:07am
Oct 31, 2021
more reports »
  • By Brionic & contributors
  • #30656 - 197 views