Cougar Mountain: Harvey Manning Trailhead

Trip

Day Hike - Cougar Mountain: Harvey Manning Trailhead

An easy after work hike to a big, REALLY big rock, the Fantastic Erratic. Hike on Cougar Mountain doing a loop from the Harvey Manning Trailhead to the Fantastic Erratic. Meeting time 4pm at the Harvey Manning Trailhead.

  • Easy, Easy
  • Easy
  • Mileage: 3.0 mi
  • Elevation Gain: 600 ft
  • High Point Elevation: 1,430 ft
  • Pace: 1.5 - 2.0 mph
  • FULL (6 capacity)
  • FULL (2 capacity)
  • Thu, Mar 26, 2026 at 9:00 AM
  • Mon, Apr 20, 2026 at 5:00 PM
  • Cancellation & Refund Policy
  • iCal Google

This is a mentored hike with a new hike leader.  We'll stay together taking breaks as needed.  We will take a couple of trails to a spur to the Fantastic Erratic where we'll take a brief break and then loop back on different trails. The steepest section is the spur to the Erratic, a drop and return climb of about 200 ft in .5 miles. We'll plan to be back at the trailhead by 6:30pm but adjust as needed.  Sunset will be about 8pm. Trails are on the Green Trails Cougar Mountain.  King County Parks also has a good map with all the Cougar Mountain trails. Sturdy water-proof footwear and trekking poles are recommended.

Meet at the Harvey Manning Trailhead at 4pm, boots on the ground at 4:15pm. On old maps it may be shown as the Anti Aircraft Peak Trailhead.   No pass is required. You can use Google Maps for the Harvey Manning Trailhead.  

Route/Place

Cougar Mountain: Harvey Manning Trailhead


Roster
Required Equipment

Required Equipment

The Ten Essentials

  • Navigation
  • Headlamp
  • Sun protection
  • First aid
  • Knife
  • Fire
  • Shelter
  • Extra food
  • Extra water
  • Extra clothes
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