This is an archived article that was published on in 2005, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.

RIDGECREST, Calif. - Our group stops for a minute under the rotisserie lamp of the high-desert sun and considers a crude, 1,000-year-old picture chipped into the sunburned lava wall. Most likely it's of an ancient holy man garbed in the headdress and robes of his sacred calling.

Or maybe not.

It's a mystery, really. Experts aren't even positive who carved more than 6,000 images on the walls of the mile-long Little Petroglyph Canyon in the Coso Mountains. What message were they trying to convey? Why this place? Were carvings sacred?

What is clear is that this canyon and others nearby are a mother lode of prehistoric pictures, the highest concentration of ancient rock art in the Western Hemisphere and a focal point for hundreds of early Americans who told their stories in stone for more than 15,000 years.

Also clear is that, because of the canyon's location on the remote, highly secure Naval Air Weapons Station at China Lake, only a few hundred people see it each year. No Space Mountain-style lines, no camera-hauling masses piling off tour buses - just you, a couple of guides, a handful of other hikers and plenty of mysteries.

Little Petroglyph Canyon is one in a group of sites in the volcanic bluffs above the Pleistocene lake bed of China Lake that, collectively, were designated as the Coso Rock Art National Historic Landmark. There might be as many as a quarter of a million rock drawings in the 36,000-acre district, all within the 1,700-square-mile China Lake base.

The base, which sits in the upper Mojave Desert just east of the Sierra's southern end, is a Navy research facility where weapons such as the Sidewinder air-to-air missile and parts of the Polaris missile were developed and tested - and where the next-generation weapon is around the corner.

So, unlike a national or state park, you can't just waltz in any old time.

But in fall and spring, the Maturango Museum in nearby Ridgecrest organizes daylong hiking tours through Little Petroglyph Canyon, the only site accessible to the public. I signed up for a fall tour in June (trips are suspended during the triple-digit summer temperatures) and was required to provide as many personal details as I did for my last car loan.

The 6:30 a.m. start time is reason enough to spend the night in Ridgecrest, which, like most base towns, has more purpose than charm, but has an ample supply of lodging. The museum is only a three-minute drive from the China Lake gate. After the 20-minute search of the cars by armed guards, the canyon is another 45 miles north and a few thousand feet up into the Coso Mountains. The last seven miles are on deeply rutted dirt roads

The difficulty in getting to the canyon and its protected location have a lot to do with the continued existence of the rock art, according to our guides.

''We're willing to put up with the hoops because we want to see petroglyphs,'' said longtime guide Jennifer Venola.

Everything around us was treeless lava flow from the still-active Coso Range volcanoes rising in the northeast. Sometime after this layer cooled, Ice Age runoff cut a channel in the thick basalt, leaving a narrow, winding corridor with sheer 20- to 40-foot walls - perfect canvases for the early artists who must have thought such a bizarre-looking place was deeply spiritual.

Venola and fellow guide Ronald Spees started our group of 10 at the top of the canyon, where the petroglyphs are fewer and more worn, impressive only by their estimated age: in the neighborhood 12,000 to 16,000 years.

The ''drawings'' are patterns the early indigenous artists created using a hammerstone to chip at the surface, revealing the lighter-colored basalt under the desert varnish, the dark layer on the outside of the basalt caused by weather and micro-organisms living on the surface for thousands of years.

We clambered over and around boulders and down flood-polished rock and sandy riverbed, wandering leisurely past the carvings, in some cases having to watch our step to avoid treading on ancient stick figures. Some dicey areas that required light climbing, coupled with the midday heat in the shadeless gorge, made the leisurely pace as much about safety as luxury.

So prolific were these ancient carvers that through much of walk there was nowhere to stand that wasn't in view of half a dozen drawings. More than half are of bighorn sheep, followed by images of snakes, the sun, birds, spirals, hunters with bows and arrows and older stick figures with an atlatl, a spear-throwing tool used by the Aztecs. It was an endless supply of messages, some shouted, some whispered, some prayed. The intent behind some glyphs was pretty obvious. Others were as mysterious and open to interpretation as the shapes of cloud.

It may be that experts are over-thinking the canyon's mysteries, according to guide Venola.

''The women were going out to gather, the men were going out to hunt and left the children in the canyon, and the last thing they said was 'I don't care what you do, just don't write on these walls,'” she said. ''It's a perfectly viable explanation.''

If you go

Getting there: Ridgecrest is on California Route 178, east of the southern end of the Sierra, 150 miles north of downtown Los Angeles.

Petroglyph tours: Maturango Museum:

General information: Ridgecrest Area Convention & Visitors Bureau, 139 Balsam St., Ridgecrest. 800-847-4830,