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Sunshine Lion's Lair Loop

 4.6 (82)
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Map Key

5.3 Miles 8.5 Kilometers



1,274' 388 m


-1,293' -394 m



Avg Grade (5°)


Max Grade (18°)

6,802' 2,073 m


5,530' 1,686 m



Minor Issues 4 days ago
Some Mud, Icy - Pretty clear, except the run back to the tailhead after crossing the road. After the road, complete shit show of ice and mud. Recommend running this final stretch down the road for the sake of your shoes and the trail. History

Getting forecast...

Great Mount Sanitas views are the reward for this gentler loop in Sunshine Canyon.

Megan W

Dogs No Dogs

Features Views · Wildflowers · Wildlife

Some parts of this loop are closed to dogs.


This enjoyable loop sees less traffic than the main attraction in this area, the Mount Sanitas Loop. The other advantages of this loop include a less arduous ascent on a shiny new trail and a quick, efficient descent.

Runner Notes

It's very smooth, runnable, non-rocky, and non-rooty on the Sunshine Canyon Trail, Lion's Lair Alternate, and Lion's Lair Trail ascent. It's steep, technical, and rocky on the Mount Sanitas Trail descent.


This loop combines several area trails into a varied, pleasant hike. Starting from the Centennial Trailhead at the mouth of Sunshine Canyon near the toilets, head south very briefly, up the road-width trail, to find the start of the Red Rocks Trail. Almost immediately, you'll leave the Red Rocks Trail and follow the Sunshine Canyon Trail as it branches off to the west and crosses a small ravine. Follow the nicely bench-cut trail, contouring Sunshine Canyon Trail as it parallels Sunshine Canyon Road. This section of low angle trail is not steep and has a mostly smooth surface, passing through fields and fir forest.

The Sunshine Canyon Trail ends at a residential driveway, adjacent to Sunshine Canyon Road. To access the next part of the loop, follow the signage and carefully cross the road (there's a crosswalk). Turn left and head briefly up the road until you reach the first dirt residential road on the right (east) side of the road. From the intersection you can see stairs indicating the start of the Lion's Lair Trail.

The Lion's Lair trail starts up a small ridgeline sparsely treed with fir. After about 1/2 mile you'll pass the Lion's Lair Spur trail, which would take you to Sunshine Canyon and a few parking spaces. Continue on Lion's Lair.

Switchback and contour up the western flank of Mount Sanitas, climbing gently past dry rocky outcrops. There are views of the Continental Divide, and down into Sunshine Canyon. The grade is never steep, and the surface is smooth. As you ascend, you enter a pine forest, and the views get better and better. Be sure to turn around and enjoy the high peaks in the distance. At the end of the trail, you merge onto the main Mount Sanitas trail for the last few feet of rocky stair-like climbing to the summit. At the summit, all of Boulder is laid out in front of you.

Take a breather before descending the Mount Sanitas Trail. This is a steep, challenging descent down the spine and western edge of Mount Sanitas. Pass over rocky sections and numerous large step-downs. Expect a lot of hiker, runner, and dog traffic on this section of trail. There are several rest spots where you can pull off to enjoy views of town and also the snowy peaks to the west. There are a few rutted steep sections with difficult footing. Towards the bottom, you'll pass some short bouldering cliffs popular with rock climbers. After one last series of tall wooden log steps, you'll cross an irrigation ditch and emerge into a small meadow. Keep to your right, crossing a stream and passing through a covered picnic pavilion. Signs will guide you. Carefully cross Sunshine Canyon Road and head uphill to arrive back at the Centennial Trailhead parking area.

Flora & Fauna

A suprisingly wonderful variety of wildflowers in the sunny spots- especially in the early spring months (April & May).


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Your Check-Ins


Feb 14, 2019
Jason Doedderlein
wonderful trail. the last stretch, once you cross the road, was a shit show of ice and mud. would have ran down the road if I'd known. If spring, o… 5.2mi
Feb 1, 2019
Sam Albert
Jan 9, 2019
Courteney Schwander
Dec 8, 2018
Ricky Davis
Done in reverse. 4.9mi — 1h 12m
Nov 4, 2018
Andrew G
Oct 25, 2018
Richard Nakano
Sketch on the way down, ITB left knee after an hour 5.3mi
Oct 21, 2018
James Carson
Down via Sanitas Valley
Oct 17, 2018
James Carson
Down via Sanitas Valley

Trail Ratings

  4.6 from 82 votes


  4.6 from 82 votes
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in Colorado


617 Views Last Month
28,352 Since Apr 23, 2015
Intermediate Intermediate

Dale Hawkins
Erie, CO
Dale Hawkins   Erie, CO
Personally, I prefer going in the opposite direction on this loop. The steep climb a pretty good workout, and then you can stretch the legs back out during the descent. Great loop though. (Probably ran it at least a dozen times this year.) Dec 9, 2015
Todd Straka
Todd Straka   Boulder
One of my favorite loops from downtown. The plush trail on Lions Lair makes for a great run. Beware of that Sunshine trail in the winter though as it can get ice packed and super slippery across the slope as its north facing. Dec 11, 2015

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