The Mud Caves

Eons ago a sea covered much of what is now southern California. Sediment covered its floor with mud. Then the sea evaporated and the land rose—or maybe it was the other way around. Either way, in a portion of the Anza-Borrego Desert there are now vast mud palisades that have been hardened by fierce sunlight into near brick-like consistency and are occasionally carved by heavy rains. Today caves and arroyos and slot canyons are found in abundance, presenting unusual formations in the starkness of the terrain.

The mud caves are located in Tapiado Canyon off a two-lane asphalt road at the end of seven miles of dirt roads covered with sand. By midday on that March day in 2000, after we had climbed Ghost Mountain in the morning Father Richard and Marge had brought me to the mud caves. In the last leg of the journey, one bounces as if driving on a large washboard, incessantly jerking the wheel to avoid rocks and ruts, and eventually comes into a narrow canyon. When I was taken there the first time, not being fully enamored of being jounced around in the back seat of a Suzuki, I was (at best) merely enduring the experience in spite of the lavish promises from the Averys. When we finally came to a place where the opening of a great cave appeared, I dropped my jaw, and breathed, “Wow!” and then stayed silent and stared.

A huge opening had appeared before me, shaped with graceful curves, swirling sharply off to the right with an entrance at foot level about eight feet wide, widening at the middle, then narrowing into closure at the top. As far as we could tell, we were at least ten miles from another living being.

We entered the great cave—technically a canyon since it was open to the sky in most places—and walked just a short distance before sitting down to picnic in the dimness a few turns from the entrance. After we’d cleaned up the lunch things, we traipsed the twisting passages throughout the length of the cave until it eventually widened out and all but disappeared.

I learned later that there are maybe two dozen mud caves in the area, several of which are easy to get to. In the company of others I have traversed several of these passageways and marveled at their graceful, water-carved contours. One has an incredible skylight thirty or forty feet above the floor of a sizable chamber. I have said Mass there on a Sunday morning for a small group.

Grateful to the Averys for revealing this wonder to me, I determined to return at the first opportunity, which turned out to be six or seven months later. The first time I had seen the cave it was a Friday, and we were utterly alone. This time it was a Saturday. When I arrived, there were about twenty Jeeps, Suzukis, Jimmys, Isuzus, etc., two tent cities, and a boy scout troop on hand. A good fifty people milled around. But when I entered the great cave, I found, surprisingly, that there was no one else there.

The previous March I had seen a small crevice on the left side of the path inside the great cave, but it was entirely dark and I didn’t go far into it. This time I planned to explore it and had intended to bring a flashlight, but realized when I was a few miles away from my destination that I had forgotten, so bought four house candles at a general store not far from the cutoff to Ghost Mountain.

This time I entered the small crevice, carrying a candle. Barely narrow enough to accommodate a human being and closed overhead with probably 40 feet of dried mud between the spelunker and the sky, I moved down the passage. It kept going, twisting and wrapping around beyond my ability to keep track of direction. I grew uncomfortable but continued. I wandered through the curves and passages, not seeing a straight line of any length anywhere.

It turned out to be a terrific passage, with skylights here and there, and a place or two where the explorers have to lift themselves up over shelves to continue the journey. This genuine cave eventually opened up on top of the palisade into a depressed place. Clearly the rainwater gathers there and over the years has carved out smaller caves on its journey to the main passage and eventually the main canyon.

It was a nearly unique place of marvelous beauty—with a smidgen of danger. Being made of mud (the technical name is “pseudokarst”), no matter how hard it may be, the walls and ceilings are subject to cave in. The floors are littered with small and sometimes alarmingly large chunks of extremely dense and heavy mud detritus that have fallen.

I have been back to Tapiado Canyon about a dozen times since 2000 and brought probably fifty people there during these visits. At the end of this month (January 2007) I will go again with about eight people to camp for two nights.

There is one last bit that may interest those who know that I wrote the nine-volume Starman series. Writing these books was a project that occupied me from 2000 to 2005. When I first saw the great mud cave, I immediately thought, “tint the soil with a little red and you’ve got Mars.” Right away I knew the scene must appear in the books of the Starman series, which I was just then beginning to write. In those books Mars is a dry planet, sun-baked for millennia, then experiencing heavy rains repeatedly for the first time in centuries. The mud palisade and the intricate mud cave system are featured in the first book of the Starman saga.

Here are two links that will provide a little more information about the mud caves, including photographs.

http://www.hiddensandiego.com/preview_arroyo_tapiado.html

http://www-rohan.sdsu.edu/~ncrawfor/2006/01/mud-caves-in-anza-borrego-desert-state_29.html