Alamo depths

In the beginning it seemed easy. From a small bridge I looked beneath me at a terraced walkway twisting down into a massive crater in the ground. The enormity of the sinkhole suggested something grand beneath the surface, and more importantly, easy passage. As we strolled down the terrace, the sound of cars from the neighborhood began to disappear. On an extremely busy street in a rather affluent part of town, our location was almost completely hidden from sight. 

Suddenly the path seemed to stop. A small crack with an even smaller metal gate stood before us. The contrast between the size of the sinkhole and this tiny doorway was vast. This is how we enter, I thought. As I crawled on all fours and aped a yoga pose to squeeze through the opening, I flashed back to lying in the torpedo tube of an MRI machine, fighting unexpected claustrophobia. I came here hoping only for a quick peek into the mythical Robber Baron Cave, but I had been lured into something more. 

After we slithered for 30 seconds, the smell became uniform and musty, the light of the October afternoon a faint glow behind us. Soon, we were able to stand. Joe Mitchell of the Texas Cave Management Association was my guide, and luckily, I caught him at a unique moment in the history of the cave. Since 1995, when TCMA assumed ownership of Robber Baron, a great amount of work had gone into restoring it, and in two weeks, the cave would finally be reopened (albeit briefly) for the Alamo Heights neighborhood to see.  

I followed Joe through the passageways as he placed miniature gauges at various locations — part of a larger experiment he was conducting on cave temperature and airflow. At the time, most of what he told me was beyond my initial comprehension. I was caught up in my own experiment with airflow — trying to make sure I was still breathing.   

While that dramedy was quietly transpiring, Joe shared some rudimentary scientific information. Robber Baron is a karst cave, which means it comprises fissures and sinkholes in Austin chalk (aka limestone) which have formed over the years through contact with water. San Antonio, sitting as it does on a sea of limestone, must stand over a potentially infinite number of these caves. To take it a step further, we each live over an enormous cave that we are aware of but take for granted — the personal drinking fountain known as the Edwards Aquifer.  

After criss-crossing for several minutes through a network of underground mazes, I once again saw the soft reflection of light. After more ersatz yoga on my part, Joe and I re-emerged, but my mind was still inside the cave. 

Maps and Legends 

Caves suggest secrecy. From Tom Sawyer to Osama bin Laden, characters fictional and real have hidden in them. But the opposite is also true — people often hide the location of caves, and therefore, the caves’ existence. This was one fact of many I learned when I met the local caving group Bexar Grotto at Chester’s Hamburgers during their bi-monthly meeting.   

Cave entrances are almost always on private property, and cave owners, understandably, aren’t fond of people dropping by for unannounced visits. Caves present liability issues, and for this reason it is even difficult for lifelong cavers to gain access to private caves. Personal relationships with cave owners are developed over years, and bringing in strangers usually isn’t worth the potential headache.  

While eating a green-chili cheeseburger, I also learned of the distinction between “cavers” and “spelunkers.” I thought a spelunker was someone serious about cave exploration, but they are viewed as reckless enthusiasts by many “cavers”: Spelunkers drink beer and litter in caves; cavers conscientiously preserve the integrity of caves and their habitat. 

I wasn’t sure where that left me. I wasn’t an experienced caver, but neither was I a mullet-sporting spelunker. Being generous of spirit, Mitchell  gave me names and phone numbers to prepare me for my own cave investigation. Fellow Bexar Grotto member Linda Palit did one better — she lent me her copy of a rare but useful book called the Caves of Bexar County by a stalwart of the San Antonio caving community, George Veni.    

Caves is a scientific book, written with the passion of a fanzine and promising the secrets of a treasure map. Hand-drawn cave maps and photos of Veni are scattered throughout the book, giving it a personal feel. Though it was written in the 1980s, it has the flavor of the 1680s, when explorers combed the Western hemisphere, believing they were the first to discover it. This sounds like hyperbole, but in exploring caves, one actually can discover places where no wo/man has been before. Take that, Cabeza de Vaca!  I thought the final frontier was outer space, but it just as easily could be a hole in the ground in a lame subdivision on the city’s ever-expanding North Side. 

Immediately, this book became my inspiration and map as I tried to rediscover the whereabouts of some of the 200 different caves Veni catalogued. Assuming I found them, there was potential for danger. What if I turned my ankle in a cave and couldn’t get out? Or worse, what if I ran into spelunkers who demanded I drink Coors Light? Thankfully, I soon had help. 

Not a Brita Filter 

Caves are often discovered during real-estate development and construction. Just as often, these caves are covered over or filled in. 

After some elementary googling, I found George Veni in New Mexico, where he works as executive director of the National Cave and Karst Research Institute. Talking to Veni on the phone, one fact became inescapably clear: The limestone underneath San Antonio is not a big Brita filter that cleans our drinking water as it percolates into the aquifer. In a sense, the caves function like arteries and veins, with the aquifer being the heart. Putting pollutants into the ground is like shooting bad smack into one’s arm; the effect is quick and can be destructive. The fact that much of our city’s new development is on the North Side, and over our aquifer, threatens our future sustainability. A Bexar Grotto member told me there are now 518 known caves in Bexar Country, a jump in almost 300 in a span of only 20 years. Intense developent is one logical explanation for this exponential increase in discoveries. 

Just as I was about to head out I got a call from Current photographer Justin Parr, who was excited to join in my fool’s errand. With my cave book and his camera, we went out to see what we could find.   

The Cave of the Flimsy Loft 

Our first challenge: adjoining caves somewhere along the cliffs of Olmos Creek, known as TMI Caves I & II. We pulled in at a public park and started moving along the creek bed. Two clues revealed their location from afar: beer cans and old picks and shovels lying on the ground. 

The first cave is a series of short tunnels that penetrat the wall of the cliff at several different points. I imagined this spot must have been a favorite back in the day for students of the former TMI academy, especially those looking to skip class and smoke cigarettes. A loft had been built into it, and a dilapidated chair was perched on the edge. In rediscovering a cave, the artifacts of human presence serve as a cheap system of historical dating, be it names written on the walls, candles, or this weird chair that I considered trying to sit in but thought better of once I realized how flimsy the plywood underneath had become.   

The first expedition was a success, though we realized we needed to bring more safety equipment for the following excursions. 

The Cave of Collapsing Fortunes 

The next cave I pursued appeared to be in the yard of a residential neighborhood on the North Side near 1604, and is known simply (and redundantly) as Cueva Cave. Veni’s book mentions that the owners had been trying to excavate the cave in search of “extensive rumored passageways” extending 1.6 kilometers to the west. A terraced walkway extended from the surface ground to the cave’s entrance, and a sturdy ladder was perched in its mouth, suggesting an invitation. 

I knocked on the house’s door with a press pass in one hand and Veni’s book in the other, as if the combination of the two would guarantee entry. But no one answered. It was getting dark, so I returned the next day with Justin to try our luck once more. 

Again, I knocked on the door, but still no answer. It became clear from the condition of the house that no one lived there, so we constructed a cheap “legal” argument for our amusement. If we were interested in buying the house, was it not fair for us to examine the landscaping of the front yard? And if a cave just happened to be in the front yard with a ladder inviting us down, was it not fair to examine this bedrock to make sure the home was built on a solid foundation? I internally answered yes — but only if we were quick. And yes, there was a ladder. 

A lighting system had been rigged underground, but we didn’t try to turn it on. We poked our flashlights around, vainly searching for “extensive passageways.” I did see a few “spelunkers’ droppings” and I removed them in an effort to leave the cave better than I found it. Cueva Cave looks to have been improved since Veni documented it, but for now it is in limbo, waiting for a new owner. Soon, we were on the road heading even further north in search of another cave that Justin had visited years before. 

Cave Park of the Apocalypse 

We drove around a far Northside neighborhood in search of our next cave, said to be located “in a field across from a brand-new school named after some asshole.” Check. 

The field appeared to be some version of a city park. Paths had been cut, but the whole place looked unfinished. A few random, crappy exercise stations were placed at various spots, along with empty sign holders. The absence of any context created an interesting feeling of foreboding.  

We began walking down the path, and immediately not one, but two caves pretty much fell into our lap. The mouth of one is covered with an intense system of metal grates. We later guessed this was Bear Cave. The other cave (possibly Cub Cave?) is almost completely exposed, and distinguished by a large, tapering overhang. It didn’t really seem like a typical cave at first — more like a place to stay out of the sun. But then we noticed an opening in the rocks and continued walking. Hunched over, we found a line of passages that continued every time we thought it was about to end. 

Beer cans were everywhere, as were cans of green tea. In a middle room, “4:20!” is inscribed on the wall. As we were about to exit we came upon another passageway leading down. With our lights shining into this opening, we determined we could easily exit, so we continued. The air grew colder, suggesting that the path kept going for a while, and additional cans of green tea hinted that we were on the right trail. Then we heard it: a strange rumbling sound. Justin and I looked at each other, and like characters in a bad action movie, I think we both said, “Let’s get the hell out of here!” 

The Great Southwest Passage 

From the list Joe Mitchell had given me, I called a few gentlemen who had explored Robber Baron as kids back in the 1930s. The first few times I phoned, their wives informed me they were taking naps, which seemed appropriately childlike for those with whom I hoped to discuss the lure of caves. 

Guy Halter (Alamo Heights Class of 1941) recalled his 1930s caving adventures in that area in great detail. His brother, he said, visited a rumored cave at the intersection of Hildebrand and Shook, now covered by pavement and hinted at in Veni’s book through the mention of a lone North San Antonio Times article. Halter also spoke of a large pit in the San Antonio Quarry, officially known as the Portland Cement Cave, but he was never able to explore it. It was later concealed, and now I imagine it hidden underneath a fairway on the Alamo Quarry golf course. 

Veni’s book mentioned other caves underneath Alamo Heights, and an intriguing legend of a network connecting them. About 700 meters from Robber Baron is (or was) a cave known as Holmgreen’s Hole, described by Veni as “potentially one of the longest caves in Texas.” The original owner of Robber Baron described being able to enter Robber Baron and exit out of Holmgreen’s Hole.  Holmgreen’s has been covered and the original property has been sold and subdivided into three lots, and Mitchell isn’t certain which of these lots contains the cave’s mouth.

Robber Baron is the most impressive and documented of these Alamo Heights caves. Though there are many stories, here are a few of the highlights: It was a commercial cave (with its own speakeasy!) during the Roaring ’20s, with an estimated 200,000 visitors passing through before it closed in the early 1930s; at nearly a mile in length it is the longest documented cave in Bexar County; two federally listed endangered species are specific to Robber Baron, one of them being the Robber Baron Cave Meshweaver Spider, Cicurina baronia

What interested me most, though, were the stories of how much longer Robber Baron used to be before the original owner blasted shut many of its passageways. A Great Southwest Passage was rumored to extend as far as the old TMI Campus, 2 miles away. That story, combined with the rumored connection to Holmgreen’s Hole, created an incredibly tantalizing scenario. 

I contacted Mitchell and politely begged to return to Robber Baron. 

Holmgreen’s or Bust

In 1981, with permission of the cave owner and the assistance of a jack hammer, Veni and a group of fellow cavers began to excavate Robber Baron in hope of extending its passageways beyond the “Mystery Breakdown,” where the cave pathway seems to have been closed. They wrote a motto on their carts: “Holmgreen’s or Bust,” but as Veni conceded in his book, “So far it’s been ‘bust.’” The walls had collapsed, and they were never able to reconnect the lost passageways. 

Justin and I met Mitchell and his wife, Evelynn (a professor at St. Mary’s University), at night for a two-hour exploration. With a greater knowledge of the history and potential of the cave, this trip took on additional meaning. More than once we saw paths that seem to stop unnaturally. Near the Graffiti Room (where there are inscriptions dating as far back as 1918) a large passageway ends abruptly. We could hear the sound of cars overhead as they traveled down the old Camino Real, and now when I drive down that stretch of road I wonder about the lost passageways and what might have been. 

Cave of Exploded Dreams 

So I thought that was it. But I couldn’t get the promise of a secret cave web out of my mind. I decided to call one more gentleman on my list of contacts. He asked me not to disclose his name or where he lives, and after hearing his incredible story, I can understand why. 

I agreed to call him “Pat.” He’s about 82 years old and explored Robber Baron as a youth as well. (He also mentioned the location of a now-closed cave entrance in San Pedro Springs Park, but that’s another cave and another legend … ) Not only had he poked around Robber Baron, but he and his father had actually built a cave underneath their house in the hope of connecting it to Robber Baron.

Pat agreed to show me the cave, and within a few hours Justin and I were at his house, which is located about three-quarters of a mile from Robber Baron — not exactly close in cave distance. He took us to the basement underneath his house, and as he turned on the light, down a hallway we could see a large hole with a ladder leaning down … into something. I believe Justin and I simultaneously looked at each other in excited disbelief. 

Though he’s had two knee operations, Pat was happy to make his way down this long, rusted ladder, joking about raccoons as he descended. He and his father were in the construction business, and with some basic knowledge of explosives, they would dynamite into the fissures. When planes flew overhead, they would fire the dynamite, and blame any noise on the “sonic booms.” It’s as if they were acting out their own scene from a prison-break movie, except that instead of trying to get out, they were trying to get in. They never found a link to Robber Baron, however, and Pat’s father was understandably disappointed. Interestingly, Pat’s father never wanted to visit Robber Baron; he wanted to see it for himself via his own cave. 

What remains of their self-made cave is still quite impressive: a large room with an additional descending loop. Justin and I explored it for several yards, but then saw a black furry animal hiding in a corner and figured we had gone far enough. 

I left in complete happiness with this new knowledge. Though Alamo Heights can be stale and lame, the history and legends of these caves — as yet fragmented and isolated — gives a new complexity to the neighborhood that will never be apparent from above. 

Don’t try this at home! Caving can be dangerous without the right knowledge and equipment. If you’re interested in learning more about San Antonio caves or exploring them for yourself, please contact the Bexar Grotto at The group meets the second and fourth Mondays of every month at Chester’s Hamburger’s at 281 North. 

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