Well-equipped rigs claw their way through the narrow, twisting entrance to Rocotillo Rapids.
The canyon is considered quite a bit "easier" now with lots of traffic in the intervening years and 40-plus-inch tires becoming commonplace. Still, Rocotillo Rapids offers more than enough challenge to leave scars and fully earn its "Extreme" rating. Narrower and more twisted than the other trails in the system, its walls close in tight enough to take bites of fenders and rear corners. Its three signature obstacles are all still there, although they continue to evolve from the passage of time, water, and tires. The initial challenge is a rough ledge running diagonally under an undercut wall. The left side offers an easier passage that allows one to dance through if the tires hit all the appropriate high points. Most of the hard-core types choose to take the more difficult center route. The undercut ledge and tire-swallowing holes often necessitate multiple attempts, and that is where the undercut wall comes into play. Get too far right, and you will certainly lose paint.
The second signature obstacle is a pair of side-by-side ledges. The original route runs to the right, but the passage of numerous vehicles has taken some of the teeth out of its former bite. The "impassable" left side gets driven fairly regularly, but on the Wednesday run this year, less than half of the vehicles were able to scale it. The third and final significant challenge is a steep climb up a large outcropping of solid rock in the canyon. Hit the right line, and one can idle up. Miss it, and things can still get ugly. Only one vehicle showed its dirty side to the sky on our recent trip, but it served as reminder that Rocotillo Rapids still provides more than enough challenge for rockcrawling extremists.
They come wrapped in all sorts of sheetmetal (or lack of it), but most vehicles on the Big Four share some common characteristics: lots of rubber, Dana 60s, and a few scars.
Tabasco Twister
Tabasco Twister is our personal favorite of the Big Four. Longer than the other routes and somewhat physically separated from the main trail system, Tabasco offers both high challenge and an uncommonly beautiful canyon. Due to its relative remoteness, it is a somewhat longer bounce through several canyons on rough dirt roads to get to the start of the fun. The stiffer challenges start with a nice warmup in an extensive rock garden. Multiple paths provide different levels of challenge to suit the driver's desire and ability.
Immediately following the rock garden is the first serious ledge. A wall of rock sits diagonally across the watercourse with a right angle in the middle of the canyon. The difficulty differs with the level of the gravel base at the bottom of the "falls," and a deep hole means high challenge. Thesharp breakover angle adds additional difficulty, but a solid winch anchor is available for the almost inevitable winch pulls.
Next up is The Abyss. Aptly named, the signature test piece of Tabasco Twister is a huge ledge stretching all the way across the canyon. The verticality experienced by drivers when their front tires reach the top of the ledge is intimidating. The propensity for the rear tires to drop into the holes at the base of the wall often has the drivers staring into the yawning voids at the bottom of the ledge. Again, a handy winch point may see a lot of use if the holes at the base are at full depth.
After The Abyss, the rest of Tabasco Twister is a pleasant drive for rock-loving drivers. There is enough optional challenge to keep things very interesting. One optional climb through a slender slot has been the scene of particularly abundant driveline carnage. The narrowing walls in the slot tend to trap the rear of the vehicles in a tight mineral grasp. The resulting load on the front end has driven many a component past its breaking point.
Tabasco Twister is also about scenery, which, at least in our opinion, is fine enough to want to drive the canyon even if it were paved. Over the many years and numerous traverses that we have made of these trails, Tabasco remains our personal favorite of the Chile Challenge Big Four.
If you are fussy about your paint, either drive carefully or stay off the Big Four. The rocks often win. | 
Trail leader Harold Off eases the front end up on the harder left side of the second waterfall on Rocotillo Rapids. | 
This diagonal ledge in Rocotillo Rapids is the first major challenge. Big holes make approaching on the right line difficult. |