Balanced precariously on a pile of rubble, we stared upward at an oval character with a gaping mouth - a green mask painted on the sandstone wall of an overhanging cliff.

The pictograph was likely Basket Maker, dating from the 3rd to 7th century, A.D. when the primitive Anasazi occupied Grand Gulch."Supposedly a mummy was found here where strips of flesh had been removed from the face, dyed green and resewn," said Ken Sleight, our guide into this remote corner of southeastern Utah.

"We know the practice existed," chimed in Grant Johnson, a wrangler working for Sleight, "because a green mask mummy was recovered from Marsh Pass on the Navajo reservation."

Both should know what they're talking about. A scholarly looking outdoorsman of about 60, Sleight is one of a handful of professional guides still making trips on a regular basis into the area. Blond, and something of a jack-of-all-trades, Johnson has worked on restoration projects in Grand Gulch in years past.

In Green Mask Canyon we were in the third day of a four-day trek, hiking as Sleight describes it "with pack stock support."

In short, the horses packed the heavy gear. While lightly encumbered with day packs, we explored every likely looking niche.

It's a nice way to go if you can afford it. Most who come here, however, carry the necessities on their backs, and anyone who has backpacked in the high desert knows what sweaty work that can be.

Grand Gulch, it seems, is more than just a striking scenic area. It is literally a treasure trove of Anasazi ruins and Indian rock art - in diversity second only to the great pueblos of Mesa Verde in Colorado and Chaco Canyon in New Mexico.

These days Grand Gulch is managed as a primitive area by the Bureau of Land Management.

The headquarters is on Kane Gulch, four miles north of Utah 95 on State Road 261 and about 38 miles southwest of Blanding, the nearest town. The trail head is also here and a permit, easily obtained at the ranger station, is required to enter the area.

The day we unloaded our horses and gear, the modest parking lot was jammed, and a check of the license plates revealed cars from nearly every part of the country. Apparently the word has gotten out that Grand Gulch is more than just a wilderness experience.

North of the headquarters, twin flat-top peaks known as the Bear's Ears dominate the landscape, and hard by this landmark is Natural Bridges National Monument. Its rocky spans, Owachamo, Sipapu, and Kachina bespeak of Indian mythology.

Some 20 miles south, Cedar Mesa plunges 1,500 feet in a striking escarpment to join San Juan River. Its coils mark the southern-most edge of the Grand Gulch Primitive Area.

From the trail head to the river, Grand Gulch snakes its way 50 miles, fed by a skein of arcane side canyons. Bullet, Collins, Todie, Spring, Sheik's, Fortress, names given by cowmen who were the first to discover the ruins. They were also the first to dig here as simple pot hunters.

Some of their collections ultimately found their way into the University of Pennsylvania Museum and the American Museum of Natural History. In the 1800s, John Wetherill, aMancos, Colo., rancher and the discoverer of Mesa Verde, also excavated extensively here, but for the aforementioned American Museum. It was through Wetherill's work that scientists became aware of Basket Maker and Pueblo Periods.

Of Grand Gulch this much is known. The earliest finds are those of the Basket Maker Period, circa 200-600 A.D. None so far predate them.

These people were descendants of nomadic hunter-gatherers, settling down to cultivate maize and squash, and late in the period, cotton and beans as well.

Skilled in the art of basket weaving, some of their cooking vessels were water tight. Their houses, found only sparingly in the Gulch, were dug down and roofed over with mud and small timbers, although their small storage cysts can be seen among the mesa tops or in the shelter of protective ledges.

Basket Makers are largely responsible for the petroglyphs etched into the sandstone or the painted pictographs which abound in Grand Gulch. The figures typically are square-shouldered, triangular, with small heads.

In the same alcove as the Green Mask there are series of such pictographs. One of them, it's believed, portrays a breached baby. An exact date for both the Green Mask and the breached baby series has yet to be determined.

People of the late Basket Maker period were driven from the canyons by drought, not to return until circa 1050. When they, or rather their descendants, re-occupied Grand Gulch, it was with a Pueblo culture spawned by the Mesa Verde people to the east and the Kayenta people to the south.

By then they had domesticated the turkey, woven cotton, irrigated crops, possessed a high degree of skill as stone masons and were adept potters.

Jean Akens, an expatriated Californian now living in Moab, was our pottery expert, having worked as a volunteer at the Edge of the Cedars Museum in Blanding.

Randomly picking up and discarding shards which abound near the ruins, she finally found a piece she liked. Rubbing the fragment between her fingers she explained: "This is San Juan or Kayenta Red Ware. You can tell by its russet color and mottled look. The Mesa Verde influence, on the other hand, shows up in the black and white and polychrome pots," she added.

Hikers find another use for shards. They place them on flat rocks, along with cording, matting and bits of sandals, as a display and perhaps a kind of votive offering.

The hike from the Kane Gulch ranger station to the first ruin at the junction of Grand Gulch and Kane Creek is not far - only five miles and the walking is easy. From Junction to Turkey Pen ruin is an additional two and a half miles. Both can be taken in a single day. I know because I've done it.

Junction is a small ruin with a couple of kivas and two or three graineries, once occupied perhaps by a single clan. Turkey Pen, conversely, occupies the better part of a great overhanging alcove.

At the base of the cliff are a handful of small stone dwellings, the remnants of a turkey pen, while on the ledge, perhaps 50 feet above the ruined village, a square ceremonial kiva clings to the sandstone wall.

Anyone familiar with Anasazi ruins knows most kivas are round, subterranean chambers firmly anchored to the ground.

The entrance was from the roof by way of a ladder. At the bottom, a small hole, the Sipapu, marked the symbolic passage from the underworld.

Why the clans of Turkey Pen ruin built their kiva on such a high perch is a puzzle. The square kiva represents the "Kayenta influence," Sleight told me. "They apparently were a people who marched to their own drummer. A restored ceremonial kiva can be seen at Perfect Kiva Ruin in Bullet Canyon.

Our own particular route took us down Grand Gulch, via Kane Creek and up Bullet, altogether a 30-mile trek over a four-day period.

April and May are the ideal months when temperatures are mild and the ephemeral streams and seeps run full.

In the spring, Grand Gulch is lush by high desert standards as globe mallow, Indian paintbrush, sweet peaks, lupines, primrose, the desert trumpet and claret cup cactus brighten the landscape.

October through the fore part of November is also a good choice. Then the gnarled Fremont Cottonwoods add their splash of color. However, it is a good idea to inquire as to the availability of water before venturing too far afield. In mid-summer temperatures can soar above the 100 degree mark and water is scarce. Unless you consider yourself an experienced desert hiker, it is a time when the canyons should be avoided altogether.

For information regarding horse tours, contact:

Horsehead Pack Trips P.O. Box 1270, Moab, Utah 84532

Horseback - Wild and Scenic, Inc. Box 460, Flagstaff, Ariz. 86005

For guided backpack trips contact:

The National Outdoor Leadership School, Box AA, Lander, Wyo. 82520

Kent Frost, Box 687, Monticello, Utah 84535

Tag-Along Tours, Box 1206, Moab, Utah 84532

For permits, brochures, area information:

The BLM San Juan Recreation Area, 435 N. Main, Box 7, Monticello, Utah 84532 (801) 587-2141