The Arroyo Tapiado Mud Caves
Tuesday, January 3, 2012 at 5:20PM 
Entrance to one of the Arroyo Tapiado Mud Caves
Nothing says “exploring” like spelunking, unless you’re deathly afraid of the dark, bats, confined spaces, or were ever trapped in a cave/enslaved by Morlocks. If any of those things bother you, then caving/spelunking is not for you, and I don’t recommend it at all. Frankly, there’s no shame in not liking caving/spelunking, because in the dark, your mind and imagination can and will play all sorts of tricks as to what you perceive. I remember one time I was deep in a cave; then my light went out. In the sudden dark, I swore that I could hear footsteps paddling softly to my location. In my haste to get fresh batteries into my headlamp, I almost dropped them all over the ground, which would have been a disaster. Of course, once the new batteries were in the headlamp, there was nothing at all to be seen or heard, but to this day, I’d still swear that something was out there.
Yep, no lie - these caves are made of dried eroded mud!
Fortunately, the Arroyo Tapiado Mud Caves in Anza-Borrego State Park are not the fear-inducing type, as they are visited frequently by locals and travelers alike. You are more likely to be a few steps back from your fellow spelunkers than you are to discover something startling in these caves, which makes it a good location to practice your spelunking skills, should you be a novice. The caves are over five million years old, and are formed by erosion. Over the years, when it has rained, the water has cut into the hills, forming the various caves and channels that you can explore. The Arroyo Tapiado (meaning: mud-wall wash) Caves are some of the best preserved and most accessible caves in the world, so if you live in Southern California, this is yet another amazing feature that is accessible in a day’s drive or less.
Directions: From county road S-2 turn out at the signed Palm Spring turnoff. You will want to head down the road (note, this is a dirt road, and you will be off-roading. I’d recommend that if you are going to attempt this that you be in some sort of 4WD or AWD vehicle, although I have seen people make it out there in standard sedans – however, the road gets very soft and sandy, so if you get stuck in your non-4WD car, don’t say I didn’t warn you!) and bypass the spur road to Palm Spring (unless you want to check out the monument), and continue down Vallecito Wash. You can then park at the intersection of the road into Arroyo Tapiado, about four and one half (4.5) miles from S-2 and explore the area on foot.
Tips: Well, these are caves. And there’s a lot of them. You should have a flashlight, and if you’re smart, some sort of helmet. The helmet will protect your head from two things: falling mud, and falling bat poo. Not all caves have bats, but all bats have caves, so there’s a good chance you’ll run into some. Remember that they’re more scared of you then you are of them; and remember that they’re on the celling, so if you do startle them, there’s a high likelihood that they will poo on you, which is not pleasant. Did I mention that these caves are in the desert? They are! You’ll also want lots of water, since you’re in the desert, and since you’re exploring, you’ll probably want some sort of safety net – a buddy, or a rope or string to find your way out should you get lost.
Dry "waterfall" in the Arroyo Tapiado Cave System
I like to take a whole day to explore the area - there’s all sorts of neat canyons in addition to the caves, so there’s plenty of things to see and do. I’ve been told that there’s purportedly ancient fossils in the caves/cave area, but either I’m blind, or these fossils have been picked clean from the caves I’ve been in (FYI, you’re not supposed to remove them, should you find them). One last thing to be aware of: Southern California is a seismically active area, and earthquakes do occur on a regular basis. Additionally, these caves are made of mud, which is not the most stable of building materials even without earthquakes. While your odds of being trapped in a cave in are probably fairly low, you should be aware that the possibility does exist, so do take what precautions you can. Other than that, have a great time, and enjoy exploring!
See you in the underworld!
More Information: http://www.desertusa.com/anza_borrego/Mud_Caves.html, http://sandiegotrailtramps.com/pages/2011Hikes/11_2_20ArroyoTapiadoMudCaves.html, http://www.signonsandiego.com/uniontrib/20050515/news_lz1x15caves.html, http://www.in-the-desert.com/mudcaves.html, http://www.anzaborrego.net/travel/AnzaBorrego/photoalbums/webalbumlarge.aspx?frmUser=anzaborrego&frmAlbum=5692356627748998993