Anderson Mill Trail [San Domingo Wash]

Take the short yet fun ride to the historic Anderson Mill in the San Domingo Wash near Wickenburg, Arizona. The relatively easy trail is only 5 miles (one way) and follows a series of old mining trails and dry river bottoms. With plenty of other mines in the area, this trip allows for plenty of exploration. The trail ends at the historic Underwood Homestead.

Last Known Status: Open Trail type: Out & back Length: 15 miles total Approx. time: 2-4 hours Traffic: Light
Permit Needed: Yes (State Trust Land) Current Info: BLM/Phoenix F.O. (623-580-5500) Nearest City: Morristown Elevation: 2215'-2907'/td> Best Time: Fall-Spring

Permits: A State Trust Land Permit is required for this trail. Permits cost $15/individual or $20 for two people and are good for 1 year. Get permits here.

Where to go:

From the junction of I-10 and Loop 101, head north for 9 miles. Take exit 11 (US-60/Grand Ave) and turn left. Continue northwest on US-60 for an additional 28 miles. In Morristown, take a right onto Castle Hot Springs Road. Cross Highway 74 and continue on Castle Hot Springs Road. After turning into an easy and wide graded road, take a left onto Mine Road after 3.3 miles. After 0.2 miles on the lesser Mine Road, you will find parking off to the right (additional parking can be found ½ mile further north along the road).


Trail Description:

From the first staging area, head north on the wide and graded dirt road. After 0.2 miles, the road will split; stay right as you enter the Little San Domingo Wash. Stay on the main trail as it heads north, ignoring any side roads that branch off. Stay right at 1.3 miles where a left will take you past an old windmill and to a small dirt track. Stay straight at 1.8 miles and again at 2.1 miles. At 3.1 miles, the trail enters a wash – follow the main path through the wash until the trail emerges again at 3.8 miles.  At 4.3 miles, the trail once again enters a wash, leaving it at 4.4 miles.

At 4.5 miles, stay left where a smaller trail leads an old mine – consider stopping here later if you have the time/want to check the mine out. Stay right at 4.7 miles and at 5.1 miles as you proceed downhill and enter the San Domingo Wash. Follow the wash as it winds eastward. Anderson Mill is off to the left at 5.4 miles. Allow considerable time to explore the ruins here at Anderson Mill. Always use caution when exploring old mining equipment and always leave things the way they are found. One of the initial features you’ll notice is that the mill, which once processed ores like pegmatite, tantalum, and niobium, appears to be built from random pieces of junk. This observation is actually true because in an email from the owner of the mill, we learned that the mill was built “from WWII surplus scrap and a few old dump truck beds”. At this point, you have two options: head back the way you came or consider taking one of the many side trips mentioned below.

Side Trips:

For further exploration of the area, from Anderson Mill, continue eastward in the San Domingo Wash. While following this wash, you’ll find a series of old pegmatite mines as well as the Underwood Family Homestead and gravesite. Reset your trip odometer as you leave Anderson Mill. The first possible side trip occurs just 0.2 miles from Anderson Mill. As the wash turns right and then back left, make a hard left uphill. After a short climb, head right at the intersection to continue to the old workings of a pegmatite mine. This mine is closed off but there is still a little bit left to see. As you continue along in the wash, the second possible side trip comes at 0.7 miles from Anderson Mill. As the wash curves left, make an even harder left onto the barely traveled rocky trail.

After a short jaunt, the trail ends at the site of yet another pegmatite mine with some ore piles and a filled in working. The third possible side trip comes just before the 1.0 mile mark from Anderson Mill. You’ll take a right off the main wash onto a steep trail. This leads to two fenced off yet, easily accessible mine adits. These two adits are perhaps the “most open” or “most significant” of all the other ones we found in the area. Just 0.1 miles later, a wash heads east from the San Domingo Wash. This trail quickly becomes impassable and after a short time exploring the area, nothing more than ore piles could be found. The final stop on this side trip is also the most significant (do only this one if you have limited time) is the Underwood family Homestead and gravesite comes on the left at 1.5 miles from Anderson Mill. Take some time to explore the old graves, the wells, and the now destroyed house where the Underwood Family once lived. Head back to Anderson Mill when you are done (or continue to explore the area at your own discretion) and then head back to the staging area from there.

Notes & Trail Ratings:

If you ride just to Anderson Mill and back, the trail is just under 11 miles – allow for about 1-2 hours to ride out and explore the mill. If you ride to Anderson Mill and stop at all or most of the side trips, the total mileage is just under 15 miles – you’ll want to allow for about 3-4 hours to fully explore everything. While this is a relatively short trip, like the name of the road implies (Mine Road), this trail is loaded with lots of neat things to check out, most notably the historic Anderson Mill. The trail is mostly easy but warrants its 3.5 rating due to occasional washouts and slightly rough rocky sections. For more history on Anderson Mill, visit our history page on it (coming soon), check out our aerial video of it, or check out this website: Overall this is a neat trail to check out if you don’t have a lot of time or just want to get out and explore!


Page last updated: 12/29/2018