Outside the mouth of the cave, hummingbirds zizz past, feeding on nectar from yellow-blossoming plants that fringe this sun-scoured cliff. Tall, cigar-shaped cardon and ocotillo cacti stand outside the cave entrance, their afternoon shadows tracing slowly across the stony ground like sundial tracks. Inside, Crosby contemplates the mural, dense with its highly charged images of beauty and violence. He is peering into a mysterious chapter of North America’s past, working at a task that has absorbed him since he stumbled across his first cave painting in 1967: piecing the puzzle together.
At a time when archaeology has become big business—and fewer scientists can mount heavily bankrolled expeditions that make, document or publicize new discoveries—the saga of Harry Crosby, a dedicated amateur who worked with no outside funding, is altogether remarkable. A high school teacher turned freelance photographer, he came upon the Great Murals by accident. “I had gone to Baja California,” he recalls, “to work on a book about the old Camino Real, the road connecting the Spanish missions.” Then, a local rancher, guiding him around the backcountry, led Crosby to a cave containing prehistoric paintings. From that moment, he was hooked, returning again and again, by mule and on foot, pushing into lost canyons and trackless mountains. In 1975, he published the definitive Cave Paintings of Baja California, a documentary account of 230 painted caves, most of which he discovered himself. In 1993, thanks largely to his efforts, UNESCO designated some of the valleys where these paintings are found as a World Heritage Site.
Starting out from Crosby’s house outside San Diego in photographer George Steinmetz’s Chevy Suburban crammed with camping gear and camera equipment, Steinmetz, Crosby and I head south down the Trans-Peninsular Highway, the only paved road that runs the length of the landmass. Baja California sits atop a tectonic fault; now-dormant volcanoes created mountain ranges, like a spine, down the peninsula. The hard volcanic rock of the mountains is layered with strata of tuff, a water-permeable stone of volcanic ash that, over time, erodes away to expose very smooth overhang roofs (respaldos), made from the denser-rock stratum above. These surfaces, it turns out, are perfect for the creation of monumental paintings—provided an artist could reach the respaldo or, in the case of taller cave ceilings, construct scaffolds to do so.
“All you have to do,” says Crosby, “is spend some time with the murals to feel their power. But what keeps me coming back is their mystery. Who were the artists? How did they manage to do this? No one can really say.” Despite a growing belief that three different human migrations appear to have passed through the region in the past 11,000 years, no serious archaeologist will hazard a theory on who the artists were.
After two days of driving, the three of us fetch up in the quiet beach town of Mulege, about two-thirds of the way down the peninsula’s eastern coast on the Gulf of California. Brick and adobe buildings stand along narrow streets illuminated by strings of small, white lights that dangle above the sidewalks. Mulege is headquarters for a team of researchers from Mexico’s Instituto Nacional de Antropologia e Historia (INAH), some of whom will accompany us into the mountains. We catch up with their lead investigator, archaeologist Maria de la Luz Gutierrez. Slim and soft-spoken, with rimless eyeglasses and dark ringlets falling to her shoulders, she spends the next two hours with us, poring over maps, photographs and notebooks.