Mother Grundy must have been one fabulous gal.

With a mountain and truck trail named after her in the hills east of Jamul, she’ll never be forgotten.

When picking roads for a San Diego day trip, it’s always nice to have a little variety; creating a route around local landmarks with distinctive names can be a fun exercise. Today’s route does just that… giving drivers and their rides a selection of challenging roads and beautiful scenery that this area of the county has in such abundance.

Check out more San Diego drives in my book, Joyrides Around San Diego.

Head east on state Route 94, east of the freeway’s end in Casa de Oro, through Jamul and out to Honey Springs Road. A real hidden gem, Honey Springs cuts through the hills east of Jamul and Lyons Valley, into the Deerhorn Valley community.

As it climbs, Honey Springs traverses rugged canyons and offers the first of many vistas along today’s route. It’s also a favorite for cyclists, motorcyclists and sports-car drivers for its twists and turns.
Since I was planning a dirt-road segment, I left the Miata in the garage and headed out in a Jeep Liberty… something that can handle the dirt but at the same time isn’t too big to make the paved curves too scary.

If you’d prefer to take your brand new BMW or Harley-Davidson out for some exercise, just bypass Mother Grundy. The rest of the route is excellent for vehicles that like twisting, paved roads.

After climbing up to the pass that enters the Deerhorn Valley area (marked by a large community sign), the road snakes around a bit more before hitting my first destination, Mother Grundy Truck Trail.

Experience has taught us that roads, like lines, have only two ends. However, sometimes in the back country they wander, split and can even be in the shape of a “Y.” Mother Grundy is one of those… some maps will show a connections to SR-94, our destination at Deerhorn Valley Road and our starting point, Honey Springs Road. We’ll leave the piece that connects (or might connect) to SR-94 for another day.

Where Mother meets Honey, there’s no standard county street sign, just a wooden marker and a collection of mailboxes. This, plus three yellow letters (“PVT”) on the street sign at Deerhorn Valley Road (the other end), prompted a call to the folks at SANGIS, the government agency that handles computer mapping for the county, to see if the road is, in fact private.

At the time I took this drive, in 2006, SANGIS, the county’s digital mapping system, reports that on her maps, Mother Grundy Truck Trail is a public road. So, I proceeded.

Right-of-way confirmed, I headed up the hill. The road skirts around Mother Grundy Peak, offering great vistas to the west and south. Lower Otay Reservoir can be seen between some of the rocky, chaparral-covered peeks.

The road itself was fairly well maintained for a dirt road, with occasional ruts caused by rains back in October. No problem for the Jeep, which stayed in two-wheel-drive throughout, but it would have been challenging in the Miata.

There’s a great variety of terrain along the trail, running through valleys, ravines and a times clinging to hillsides. Several ranches are scattered along the early going, with more density as the thoroughfare gets closer to Deerhorn Valley Road. There’s even a castle and the Beacon Hill Llama Farm. It’s a very unique and seldom seen side of San Diego.

Now, about Mother Grundy. Turns out, there wasn’t a Mrs. Grundy, just the Madre Grande. It’s a peak named by early Spanish or Mexican settlers because there are rocks that look like a woman’s face. In his book San Diego County Place Names A To Z, Leland Fetzer relays a story from an earlier book, Dorothy Schmid’s 1963 “Pioneering in Dulzura.”

“Madre Grande looks more like Mother Grundy to me,” said resident Claire Hagenbuck, and from then on, it was Mother Grundy. Fetzer doesn’t have a date for the name change.

After my trip over Mother Grundy Truck Trail, I made a right and cruised down to the end of Deerhorn Valley Road, instead of immediately turning back to Honey Springs Road.

Fetzer, again citing Schmid, says that this area got its name from early settlers John and Albert Walker, who once found two dead bucks, their horns locked. “The double horns, thrown into a tree, marked the place,” wrote Fetzer, citing Schmid.

Back on Honey Springs Road, it was back to fun driving. Generally heading west, Lyons Valley and Japatul roads are among the best drives in the county.

At Loveland Reservoir, I was surprised to see the water now lapping at the road; the water level raised by the 2004-05 winter storms. The last time I’d visited, I’d had to hike a half-mile to reach the shore.
A small side trip provided an even more spectacular view. Sequan Truck Trail is paved and runs along the ridge top, giving a full vista of the lake.

From there, I continued down to Dehesa Road and the Sycuan Indian Reservation for some lunch and a break from the road. I’m not much of a gambler, but did leave a couple of bucks in the slot machines after enjoying a good meal.

Harbison Canyon was next on the itinerary to check on rebuilding progress. This area was devastated by the Cedar fire in 2003. It’s good to see new homes along the route; it will take longer for the trees to grow back. Interstate 8 is just north and its time to go back home.

This has been a long drive — more than 60 miles. Although the population has been growing, there aren’t a lot of people that live in this area between Interstate 8 and SR-94. It is one of the most rugged areas of this rugged county, great for exercising your vehicle’s suspension and your driving skills.

Keep it safe and enjoy the ride.

Route and Info

  • From December 2005


  • About 62 miles.


  • Moderate. Mother Grundy Truck Trail is a dirt road; high ground clearance vehicle advised. Sharp curves throughout route.


  • State route 94 east to Honey Springs Road (east of Jamul).
  • Left at Honey Springs Road.
  • Right at Mother Grundy Truck Trail (just past “Deerhorn Valley” community sign). Note: To bypass the dirt segment of today’s route, continue on Honey Springs Road, making a right at Deerhorn Valley Road.
  • Right at Deerhorn Valley Road. Turn around at “End County Maintained Road” and backtrack (past Mother Grundy Truck Trail) to Honey Springs Road.
  • Right at Honey Springs Road.
  • Right at Lyons Valley Road.
  • Left at Japatul Road.
  • Left at Sequan Truck Trail. Take road to end, turn around and return to Japatul Road.
  • Left at Japatul Road.
  • Left at Dehesa Road.
  • Right at Harbison Canyon Road.
  • Left at Arnold Way.
  • Left at Alpine Boulevard to Interstate 8.


  1. Regardless of what SANGIS or anyone else says, Mother Grundy is a private road. The county does not maintain it and if if wasn’t for the residents, it would get washed out and not be drivable. You basically are driving through people’s front yards and for that reason it is appreciated if you do not trespass on anyones property. It in fact is an area that undocumented immigrants come through so the border patrol and sheriff can be seen from time to time. Speeders are not welcome and could encounter various situations that could put the residents and their animals at risk besides themselves.

    1. I only take roads that are on the county maps, and this one is. The story’s been around for a decade, so any traffic or problems you’re experiencing probably aren’t from here.

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