Blair Valley Loop

Total Miles 7.9
Technical Rating
3 Easy
Best Time Spring, Summer, Fall, Winter
Trail Type Full-Width Road
Accessible By
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Trail Overview

Blair Valley Loop is a 7.9-mile point-to-point trail rated 3 of 10 within the California Anza-Borrego Desert State Park. Blair Valley area is a collection of two small valleys with several attractions to see. The trip around the loop road through these valleys passes three major attractions. The most popular is the hike to Ghost Mountain to see the ruins of the Marshall Smith home. This trail is located on the southwest corner of the loop. There are two attractions on the southeast corner of the loop. The first is the hike on Morteros Trail to the remains of an ancient native settlement where you'll find several big rocks with morteros. Morteros is the Spanish word for mortar holes, or grinding stones used to process seeds and plants. The area was a seasonal home for Kumeyaay ancestors who harvested the desert agave and juniper berries found in this area and processed the foods they gathered at this site. The third is the road to the Blair Valley Petroglyph site. The trail consists of hard-packed dirt and some sandy wash areas. The loop trip through Blair Valley starts off Highway S2, which is located in Blair Valley itself. After passing through Little Blair Valley, the route returns to Highway S2 in Earthquake Valley, less than a mile from where the route started. The area has limited cell phone coverage and the nearest services are located in Borrego Springs.

Photos of Blair Valley Loop

Difficulty

The trail consists of loose rocks, dirt, and sand with some slick rock surfaces and mud holes possible. No steps are higher than 12 inches. 4WD may be required, and aggressive tires are a plus.

History

History of Blair Valley: The Indian village on the Morteros Trail was seasonally occupied by the Kumeyaay Indian Tribe for nearly 1,000 years. Morteros, the grinding holes dug out in the boulders, were made by the women as they crushed seeds for their meals. Marshall South and his family lived on Ghost Mountain for 16 years in the 1930s and 40s. The home is made of adobe and they called it Yaquitepec. Marshall was a writer and poet who supported his family by writing monthly articles about what it was like living on Ghost Mountain for Desert Magazine. In 1947, his wife divorced him and the family left the homestead.

Technical Rating

3

Status Reports

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Human Family
Nov 23, 2025
Open
Not so dusty as rains just stopped yesterday. Very easy trail for the most part.
Martin Martinez
Oct 12, 2025
Open
Started from the south (where the campsite is) and drove to the pictographs and back. Super easy trail until you drive past the junction and head towards the pictographs. Road sorts splits, is uneven and since I don’t have the highest clearance I just had to be a little extra careful. The entire road is only wide enough for one car, with very few turn outs spaced out far from each other. I have a small car and would still have some branches hit my car, so wider vehicles will definitely be hitting those. SO beautiful at golden hour and sunset. Lots of cactus especially near the pictographs
Nick Lopes
Oct 12, 2025
Open
Felix Rodriguez
May 25, 2025
Open
Andrew Padilla
Apr 19, 2025
Open
Recently graded and very easy, even for 2WD.
Bryan Kowalske
Apr 15, 2025
Open
Jose R.
Jan 19, 2025
Open
Jeff Higashiyama
Jan 10, 2025
Open
Groomed dirt road. Dried ruts around campsite area.
Charles Addie
Nov 25, 2024
Open
Defend! R
Aug 31, 2024
Open
Rob Rainney
Apr 28, 2024
Open
The cactus blooms were incredible. This was an easy loop with some great scenery.
Jeff SR G
Mar 09, 2024
Open
Easy trail but if you don’t pay attention you will get into a rut or two. Don’t get to comfortable. 👍
Kyle F
Feb 23, 2024
Open
Sand and dirt roads. One vehicle wide with several turn out areas. Saw a Honda Odyssey and Toyota Prius on the trail. 4H recommended but not needed. Lots of camping spots off the trail.

Blair Valley Loop Trail can be accessed by the following ride types:

  • High Clearance
  • Full Width

Blair Valley Loop Map

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