21.5 miles
Distance
4,619 ft
Climb
-4,624 ft
Descent
1,821 ft
High Point

Great tour of Big Rock Ridge and Loma Alta, featuring amazing views, lots of climbing, and 3 classic Marin Singletracks.

Detailed Description
22 mile Big Rock & Loma Alta Tour. is a 22 mile popular easy route located near Lucas Valley - Marinwood California. This mountain bike primary route can be used both directions and has a moderate overall physical rating. This route includes 5 trails. This route climbs 4,619 ft with a max elevation of 1,821 ft then descends -4,624 ft.

11 Reviews & Comments


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Trails in Route

Details

  • Riding area
  • Primary Activity
    Mountain Bike
  • Other Activities
    • E-Bike
  • Difficulty rating
    Green
  • Route Type
    Loop
  • eBike Allowed
  • Direction
    Both Directions
  • Physical rating
    Moderate
More Stats for 22 mile Big Rock & Loma Alta Tour. mountain bike route
  • Avg time
    3 hr 33 min
  • Altitude min
    103 ft
  • Altitude start
    121 ft
  • Altitude end
    115 ft
  • Grade
    -0%
  • Grade max
    -55%
  • Grade min
    71.3%
  • Distance climb
    9 miles
  • Distance down
    11 miles
  • Distance flat
    4,603 ft
Avg: 5 (1 votes)
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Trail Conditions
  • Unknown
  • Snow Groomed
  • Snow Packed
  • Snow Covered
  • Snow Cover Partial
  • Freeze/thaw Cycle
  • Icy
  • Prevalent Mud
  • Wet
  • Variable
  • Ideal
  • Dry
  • Very Dry
Trail Flow (Ridden Direction)
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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
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  • 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.
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  • popular
  • less popular
  • not popular
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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
  • Snowmobile
Winter Trails
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x Missing Trails
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Least Popular
Trails are colored based on popularity. The more popular a trail is, the more red. Less popular trails trend towards green.
Jump Magnitude Heatmap
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17
Big Rock Trail / Marin County Flow &...
Big Rock Trail / Marin County Flow & Switchbacks
7:15 | 220 | comments: 0 | favs:
Feb 8, 2022
680 Trail - Top Down
680 Trail - Top Down
trail: 680
20:33 | 764 | comments: 0 | favs:
Jan 1, 2019

Recent Trail Reports Along Route

statustraildateconditiondescription
Luiz Ranch Fire road
Apr 19, 2024 @ 9:15am
Apr 19, 2024
Chicken Shack Fire Road
Jan 14, 2024 @ 3:27pm
Jan 14, 2024
Big Rock Trail
Mar 25, 2023 @ 3:14am
Mar 25, 2023
680
Nov 23, 2022 @ 7:52pm
Nov 23, 2022
The Berms on the top are brand new, some to wet for Riding.
Loma Alta Fire Rd.
Jun 29, 2022 @ 9:09am
Jun 29, 2022
more reports »
  • By capttcs & contributors
  • #35923 - 658 views