Las Tres Piedras, commonly called Joaquín Rocks, is identified by three prominent sandstone rock outcroppings, La Piedra Del Oeste , La Centinela and La Catedral Grande that set at the southeast corner of Joaquín Ridge. A map of Las Tres Piedras is shown below.
Map of Las Tres Piedras (click map for larger view)
Aerial Photograph of Joaquín Rocks
These rocks, composed of Vaqueros Sandstone, were formed beneath the ocean 35 million to 40 million years ago. The north-eastern slope of each of the three rocks, consists of smooth, bare stone, with small water erosion holes scattered about. We also find the remnant of what some people believe is an ancient streambed along the northeast edge of the rocks. In sharp contrast, the south-western face of each rock presents a far different appearance. Exposed to the force of the prevailing northwesterly winds and storms, the almost vertical western face of each rock has been carved into a series of fantastic shapes, with innumerable small holes and caves that create habitat of bats and of birds.
Northeast Face of Joaquín Rocks
As shown in, there are actually four large rock on the ridge but since the fourth rock sets lower on the ridge it is not noticeable from the San Joaquín Valley, but can be seen from Cantua Creek.
West Face of Joaquín Rocks
La Piedra Del Oeste
Although not the tallest, La Piedra Del Oeste is the largest of Las Tres Piedras and the top of this rock is flatter than the others.
There is a large hole, much larger that La Tinaja Grande on top of La Piedra Del Oeste. There is also a smaller hole near the southeastern corner with a natural wall that forms a comfortable fort-like sentry post for viewing Joaquín's Flat.
There is no obvious trail leading to the summit of La Piedra Del Oeste. However, the easiest way to get there is from its southeastern side. If you are using a GPS unit, you can easily climb onto the rock at the following approximate coordinate:
You can get to southeastern side of La Piedra Del Oeste by doing one of the following:
Once you are on the face of La Piedra Del Oeste, work your way towards its center and begin your journey up the rock. Walk carefully as the surface can be very loose and slippery. Also pay attention to your path so that you can return safely.
La Centinela is the center and tallest rock of Las Tres Piedras. It was given the name "La Centinela" because legend has that Juan María López (Ojo de Águila - Eagle Eye ) built a small stone shelter on top of this rock. According to the story, Ojo de Águila functioned as a sentinel for Joaquín Murrieta whenever the gang was camped at Arroyo Cantúa or at Campo Del Árbol Del Roble in the valley below. The story also alleges that signal fires were maintained here and on nearby Black Mountain.
Southwest Face of La Centinela
You hike to the top of La Centinela by first hiking through the pass to the north corner where you can get on the rock. You will notice a mildly worn path that leads up the rock to the summit. Follow the path carefully as the surface is very steep and slippery.
Trail up the Northeast Face of La Centinela
La Tinaja Grande
La Tinaja Grande is a large hole found on top of La Centinela. This holes has about an 8 foot circular opening and is about 10 feet deep. The inside is shaped somewhat like the inside of flower vase having a larger inner diameter than the opening. This hole fills partially with water during winter rains (perhaps 1 to 2 feet of water).
La Tinaja Grande as well as many other similar, but much smaller holes are vernal pools during the winter and early spring and provide habitat for the vernal pool fairy shrimp . These shrimp live a very short time and lay eggs (called cysts) that can withstand long periods of dry heat or cold. Once the pool fills again with water the eggs hatch and mature very rapidly to start the cycle all over again.
There are stories that members of the Murrieta gang used these pools for drinking water while visiting Las Tres Piedras. Certainly the water from these pools is potable, but it is a very limited seasonal supply that is available only during the rainy winter season and early spring.
The photo below show a picture of Ray (the author of this report) standing on Las Tres Piedras Trail as it passes between La Piedra Del Oeste and La Centinela. Within this space is a large boulder called the Bull . Ray's camera is resting on the Bull for this self-photograph.
Photo of Ray Standing Behind "The Bull"
Photo of "The Bull"
La Catedral Grande
La Catedral Grande is the smallest of Las Tres Piedras and probably the only rock that is impossible to circumnavigate because its southeast wall is a shear cliff that drops down into Dómengine Creek Canyon. Richard and Jim reached the summit of La Catedral Grande during our October 2001 trip and reported that it is unwise to attempt this summit without rock climbing experience.
Richard and Jim Sitting on top of La Catedral Grande
The Temple Door
The Temple Door is located on the northwest wall of La Catedral Grande in the narrow pass between La Catedral Grande and La Centinela.
Trail Between La Catedral Grande and La Centinela Leading to the Temple Door
Photo of Temple Door Guarded by "Saint Peter"
It can be seen in the photo above that someone has ground the back wall of this rock shelter; I suppose that it was originally ground flat by Mariana. While standing in front of the oval concretion nodule called "Saint Peter" (the rock in the middle) you almost begin wanting to believe that this really is some kind of doorway.
The Conglomerate Bed
What appears to be an ancient river bed exist just above the base of the northeast side of La Centinela. This apparent bed consist of small golf-ball size erosion-worn stones. However, this is not the real river bed, but is instead a rare conglomerate bed that formed beneath the ocean.
Photo of the Tumbled Rocks Near the Base of La Centinela
Photo of Concretion Nodules
Copyright ©, 2005; Updated May 23, 2016