Trail Run Project Logo

Los Alamos Natural Arch Out-and-Back



4.3 mile 7.0 kilometer out and back
88% Runnable


Ascent: 806' 246 m
Descent: -805' -245 m
High: 8,022' 2,445 m
Low: 7,217' 2,200 m


Avg Grade: 7% (4°)
Max Grade: 48% (26°)


Driving directions Take a virtual tour
Zoom in to see details
Map Key

Trail shared by Bill Blumenthal

A nice out-and-back with great vistas leads to a natural rock arch.

Bill Blumenthal

Features Birding · Fall Colors · Spring · Views · Wildflowers · Wildlife


The run uses the Perimeter Trail and the Mitchell Trail #69 to reach the popular natural rock arch above the townsite. This one is accessible from spring until fall when snow and ice are not present; however mid-summer will be very hot with little shade.

Need to Know

Always bring plenty of water, sunscreen, a hat, and especially a camera. During the summer, lightening from thunderstorms is a hazard on exposed ridges. Be aware of flash flooding in the summer, even when no rain is falling.


Park along Maple Drive about 500 feet north of the intersection of Maple Drive and Sumac Lane in Ponderosa Estates (Los Alamos). There is no trailhead signage at this location, so look carefully for the start of the trail adjacent to a house heading west along the south side of the canyon at the sharp bend in the road.

The Perimeter Trail shortly intersects several other access trails. Always bear right heading in a westerly direction along the side of the canyon in this section. The trail gradually rises and is separated from nearby houses by a low ridgeline so that runners enjoy a measure of solitude. However, this narrow singletrack is also a very popular with mountain bikers, so listen for oncoming traffic and be prepared to step off the trail for safety.

In about 1.3 miles, the trail intersects the Mitchell Trail #69 for a few yards. Several wooden signs help guide the runner over a low ridge and back onto the Perimeter Trail which then traverses the Western Perimeter. Proceed over a low ridge and continue straight when the Perimeter Trail heads to the right. Skirt below a water tank and make a crossing of a dry stream channel. The trail continues up the dry canyon bottom. Look for rock cairns and logs on the north side of the trail marking a side trail that climbs steeply to the Los Alamos Natural Arch.

The very popular Natural Arch Trail is 0.2 miles and an ascent of 300 feet. The rock arch forms a great picture frame for views of the Sangre de Cristo Mountains and the townsite. It also provides much needed shade in the hot summer months. After visiting the arch, proceed east down the old Mitchell trail 0.5 miles until it intersects the Perimeter trail. Continue heading east on the Perimeter Trail to the trailhead in about 1.3 miles to complete the loop.

Run this trail?

We need help with the following missing trail information:

Dogs Allowed, Flora & Fauna, Runner Notes, History & Background


Rate This Run

Rate Quality

   Clear Rating

Rate Difficulty

Share This Run

Check In



Trail Ratings

  4.5 from 2 votes


in Los Alamos


  4.5 from 2 votes
5 Star
4 Star
3 Star
2 Star
1 Star
Run Rankings


in Los Alamos


in New Mexico


43 Views Last Month
1,602 Since Dec 3, 2017



Los Alamos Natural Arch looking northwest.
Dec 4, 2017 near Los Alamos, NM
Los Alamos Natural Arch looking southeast.
Dec 4, 2017 near Los Alamos, NM


Trail Run Project is part of the REI Co-op family,
where a life outdoors is a life well lived.

Shop REI Running