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greenBlue Lion's Lair Trail

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2.2 mile 3.5 kilometer point to point
89% Runnable


Ascent: 711' 217 m
Descent: -40' -12 m
High: 6,807' 2,075 m
Low: 6,113' 1,863 m


Avg Grade: 6% (4°)
Max Grade: 16% (9°)


No Dogs
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Trail shared by Nick Wilder

Fantastic views from a smooth, well-built trail.

Nick Wilder

Features Views · Wildlife

Runner Notes

This is an unusually smooth and well-graded trail. It is much more runnable than every other trail around Mt. Sanitas, and good loops can be formed if you use Sunshine Canyon Drive to connect to Sunshine Canyon Trail.


The trail was completed in the fall of 2014 and is a great addition to the area. Starting from the small parking area, take gentle switchbacks through the ponderosa forest. The grade is never steep, and at least for now, the surface is impeccably smooth. The corners and water crossings show off just how well this trail was constructed.

As you ascend, the views get better and better. Be sure to turn around and enjoy the high peaks in the distance. From the top, all of Boulder is laid out in front of you. Return the way you came, or make a long loop by going down the Sanitas Valley Trail or the Mount Sanitas Trail, then follow the Sunshine Canyon Trail back towards the beginning of this trail.

It's a shame this trailhead does not connect to Sunshine Canyon Trail (there's private property in the way), but maybe someday the county will get an easement to connect them?

Flora & Fauna

The trail name is no accident - this is one of the most frequent areas to spot mountain lions. The trails are closed a few times a year after a lion has killed a deer. You would have to be very lucky to see one... but be aware they're out there!


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Apr 8, 2019
Nick Graham
Biked to and from the trail, ran/walked the climb, took about 5 minutes of combined rest, and ran the downhill. Need to pace better on the climb. 4.5mi
Apr 15, 2018
Mike G
Mar 18, 2018
rob hudson
Jul 19, 2017
Courtney Peck
4.2mi — 0h 50m
Mar 25, 2017
Alyssa Countway
Ran up lions layer trail. Down the east side of Sanitas (almost to the bottom) and back up to the summit. And back down to sunshine 5.2mi
Mar 13, 2016
Lovely run, stays shaded in the morning and makes for a great steady, runnable climb. 2.2mi — 37h 59m
Aug 16, 2015
Gus Delaporte
Aug 9, 2015
Gus Delaporte

Trail Ratings

  4.6 from 17 votes


  4.6 from 17 votes
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15,033 Since Jan 27, 2015
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