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Lion's Lair Trail



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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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. Alternatively, you can make a long loop by going down the Sanitas Valley Trail or the Mount Sanitas Trail, then follow the Sunshine Canyon Trail back toward the beginning of this trail. At the end of the Sunshine Canyon trail, follow the signs to cross the road and travel about 30 feet to the stairs that mark the start of the Lion's Lair Alternate trail; turn left at the intersection with Lion's Lair to get back to your car.

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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Jan 26, 2020
Emily Goodin
4.5mi — 1h 00m
Jan 12, 2020
Emily Goodin
Parked at the hairpin curve on Sunshine Canyon Rd and went up Lion's Lair Spur and Lion's Lair to the Mt Sanitas peak, and back down the same way. 4.5mi — 1h 00m
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

Trail Ratings

  4.7 from 18 votes


  4.7 from 18 votes
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in Colorado


117 Views Last Month
17,031 Since Jan 27, 2015



Sunrise from Mt Saintas
Nov 3, 2017 near Boulder, CO
Rolling on Lion's Lair Trail.
Nov 24, 2015 near Boulder, CO
View looking west.
Jan 3, 2016 near Boulder, CO
The top of Mount Sanitas looks out at the beauty of Boulder and the Flatirons.
Apr 12, 2017 near Boulder, CO
Looking east from the summit at sunrise.
Dec 2, 2018 near Boulder, CO
Arriving at the summit, just missed the sunrise.
Dec 2, 2018 near Boulder, CO


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