Anthropomorphic pictograph, El Vallecito. A caretaker will perhaps help guide you along a looping mile of easy trail that visits several natural-rock shelters adorned with pictographs.

Dozens of sites featuring Indian pictographs (painted figures on rock) and petroglyphs (carved designs on rock) can be found in greater San Diego County, but only one is served by a freeway exit named for the site itself. The site is "El Vallecito," near the San Diego/Imperial County line but distinctly within Baja California. The freeway — actually a limited-access toll road — is Mexico's newest version of Federal Highway 2 between Tijuana and Mexicali.

At a point on the toll road 34 miles east of Tecate and just shy of the village of La Rumorosa, exit the toll road at "Vallecitos," turn right, then make a 180-degree turn to cross north under the toll-road overpasses. Continue north on a dirt road about one-half mile to the entrance to the El Vallecito Archeological Zone, a project of INAH -- Mexico's national archeological and historical agency. The site lies in a gentle valley at around 4000-feet elevation dotted with pinyon pines and punctuated by eroded granite boulders and outcrops.

A caretaker at the site will accept a small fee and perhaps help guide you along a looping mile of easy trail that visits several natural-rock shelters adorned with pictographs. Vandalism has been a problem in some of the larger, more elaborately adorned shelters. As a result, they're surrounded with fencing and accessible only to groups accompanied by the caretaker or a guide.

Ancestors of today's Kumeyaay Indians are thought to be originators of the red-, black-, and yellow-painted designs, ranging from expansive sun symbols to abstract designs to cartoony anthropomorphic figures. Some, if not all, are surmised to have been the work of shamans under the influence of hallucinogenic substances. One devil-like figure on a shelter wall was painted in the exact spot where the rising winter-solstice sun casts a spear of light across the figure's beady eyes. Some pictographs and certain features either naturally or artificially carved in the rock are apparently associated with puberty and fertility rituals. For example, we discovered a "yoni," a likeness of female genitals formed in the cracked surface of a granite boulder, right alongside the trail.