JURASSIC LARK

The bluffs and hills on the outskirts of this mountain biking hub were as red as a sunburn and barren, save for a few juniper trees and clumps of rabbit brush.

As I hiked up a gentle slope to a flat stretch of sandstone, I saw them -- bigger and more clearly defined than I had expected. Dinosaur tracks. I crouched by the gnarly three-toed prints and ran my fingers along the curve of the claw and pressed my palm inside the hubcap-size impression. It was a creepy feeling occupying the same spot as an SUV-sized lizard that could have devoured me like a squirming chicken McNugget.

When the giant meat eater, probably an allosaurus, walked across this spot about 150 million years ago, the landscape was vastly different, a tropical environment on the shores of a vast inland sea, lush with ferns, cycads, conifers and ginkgo trees. Here, the beast’s feet sank into a sandbar. Over time, seismic forces buried, solidified and then pushed that sandbar to the surface, retaining in astonishing detail the prints of that long-extinct monster.

It’s a happy geological fluke that made Utah one of the world’s best spots to hunt for dinosaurs. Layers of sedimentary rock hold clues to the lives of prehistoric plants and animals.

Throughout much of the rest of the country, this fossil-rich layer is buried under prairies and forests. But not in the badlands of Utah, where the stratum rests near the surface, even along hiking trails like this one near Moab, a 10-hour drive from Los Angeles.

As a result, Utah’s museums have easy access to a treasure trove of clues to the Earth’s distant past.

With plans to see Utah’s best dinosaur exhibits, I consulted several of its top paleontologists on the best way to make a four-day road trip across the Beehive State.

Dinosaur experts, almost giddy with excitement, told me now is the best time to visit, during an era of astounding discoveries. Thanks to improved research technology and an exploding interest in the field, paleontologists are digging up new dinosaur species around the world at a rate of 10 to 20 each year.

Utah’s quarries have been at the forefront of this trend, producing such discoveries as a strange duck-billed herbivore, a new horned quadruped, plus evidence that some dinosaurs tried to fish.

So in early September, I drove the length and breadth of Utah -- 978 miles -- past red bluffs, towering hoodoos and multicolored mesas. Here are my favorite stops.

ST. GEORGE DINOSAUR DISCOVERY CENTER AT JOHNSON FARM

Eight years ago, Sheldon Johnson, a retired optometrist, was prepping a parcel of land for resale outside of St. George when he spotted something in the soil. About 20 feet below the surface he uncovered thick mudstone slabs imprinted with thousands of dinosaur prints, including skin impressions and tracks from what paleontologists believe was the lanky, fast-moving coelophysis of the early Jurassic period.

Instead of yanking the solid slabs from the ground, Johnson notified paleontologists and city officials, who later built a museum around the 200-million-year-old impressions. Among the exhibits is the world’s largest single slab of stone containing dinosaur prints, a block weighing more than 26 tons.

From unearthed bones, paleontologists learn about the size, anatomy and diet of a dinosaur, among other characteristics. But from track prints, experts get clues on dinosaurs’ movements -- how they sat, ran, turned and hunted. Andrew C. Milner, the city’s paleontologist, believes scratch marks on several slabs suggest some dinosaurs swam in the shallows pursuing fish.

During a close look at a rare dinosaur skin impression, I got the frightening image of a lizard-skinned beast the size of a semi-truck stomping across the landscape.

The drive: I started in the heat of Las Vegas and drove two hours across mostly arid desert along Interstate 15 to St. George in the southwest corner of Utah.

The vitals: Open 10 a.m. to 6 p.m. Mondays through Saturdays. Admission: $5 for adults, $2 for children. 2180 E. Riverside Drive, St. George; (435) 574-3466 or go to www.dinotrax.com.

Mill Canyon Dinosaur Trail and Copper Ridge Dinosaur Trackway

Hiking along a gravel path, I stopped to examine a sandstone shelf, the earth grainy and tinted rusty and brown from oxidation. I had driven 13 miles north of Moab to a hiking trail on U.S. Bureau of Land Management territory in Mill Canyon. And there, exposed to the mercy of the elements and curious visitors were dozens of dinosaur bones, black, gray and grainy, like wood. The disjointed bones jutting out of the shelf were part of the vertebrae of a 20-ton camasaurus, according to an interpretive sign near the bones. Nearby, I ran my hands over a diamond-shape bone embedded in rock -- the femur of an allosaurus, a smaller cousin of the terrible Tyrannosaurus rex.

The BLM’s policy about fossils on public land is a bit schizophrenic. The bureau installs interpretive markers on the sites but doesn’t post roadside signs for fear too many visitors will “love the fossils to death,” according to BLM officials. As a result, only the most determined visitors see the fossils. As a favor to the BLM, I offer this warning: Damaging or removing a dinosaur or other vertebrate fossil from state or federal land without a permit is illegal.

The nearby Copper Ridge Dinosaur Trackway was slightly easier to find. After hiking about 100 yards up a marked trail from a gravel parking lot, I came to several 150-million-year-old prints on a flat rock path, as clear as if they had been made that week. The three-toed allosaurus prints cross the path diagonally, but the bigger prints, probably made by a apatosaurus, seem to make a sharp right turn, a move that paleontologists say is highly unusual.

The drive: Take your time driving Interstate 70 across the heart of Utah from St. George to Moab. Don’t rush the views of chocolate hoodoos and sherbet-colored mesas, and don’t miss the spectacular vista of Castle Valley at a rest area near mile marker 104. In the afternoon sun, the valley shone pink, green and gray under a partly cloudy sky.

The vitals: Both track sites are open year-round. For Mill Canyon, take U.S. 191 north from Moab for 13 miles and turn left on Mill Canyon Road after passing mile marker 141. After reaching a T in the dirt road, turn left and look for a gravel parking lot and an interpretive sign. For Copper Ridge, drive past mile marker 148, along U.S. 191, about 23 miles north of Moab, then turn right on the next dirt road and follow the signs for two miles to a gravel parking lot. For more information, contact the BLM’s Moab Field Office, 82 E. Dogwood, Moab; (435) 259-2100 or go to www.blm.gov/ut/st/en/prog/more/cultural/Paleontology/canyon_country_p aleontology.html

Cleveland-Lloyd Dinosaur Quarry

Beginning in the 1930s, near the tiny town of Cleveland, about 30 miles south of Price, paleontologists started to uncover the densest collection of fossils in the world -- more than 12,000 bones in one-quarter of an acre. But more surprising than the sheer number was the mystery raised by the finding. Why so many bones in one spot? And why are most of the bones from juvenile and adolescent carnivores such as the allosaurus?

Fewer than 30% of the bones came from herbivores. And why have paleontologists been unable to find an intact skull among the stockpile? Some paleontologists suggest the land was once a muddy bog that trapped herbivores and attracted predators. But that still doesn’t explain the preponderance of predator bones.

As I stood in the quarry’s visitor center, I jokingly offered head paleontologist Michael Leschin my theory on the mysteries: “Maybe it was a Jurassic fight club. The bones are the remnants of the losers.”

Without smiling, Leschin replied, “We’ve looked into that theory. If it was a fight club, what happened to the skulls?”

Outside the visitor center, I stepped into a corrugated metal shed that shelters a dinosaur excavation quarry. The pit inside was littered with bones, some authentic dinosaur fossils and some replica casts made to represent bones already removed from the hole. It looked like the remains of a mass grave, except for the fossilized dinosaur egg found here in 1987.

The egg blows apart my fight-club theory.

The drive: To reach the quarry from Cleveland, you must drive 12 miles along unpaved, washboard roads. A four-wheel drive vehicle is recommended, though not absolutely necessary.

The vitals: Open 10 a.m. to 5 p.m. Monday through Saturday and noon to 5 p.m. Sunday from Memorial Day to Labor Day. Open Friday through Sunday in fall and spring. From November to mid-March, the quarry is closed. Admission: $5 for adults. Children younger than 16 are free. Take Utah Highway 10 south to the Cleveland/Elmo turnoff and follow the signs. For more information, call the BLM office at Price at (435) 636-3600 or go to www.blm.gov/ut/st/en/fo/price/recreation/quarry.html.

Utah Field House of Natural History

In northeastern Utah, the visitors center at Dinosaur National Monument in Jensen is considered one of the state’s premier fossil viewing sites. Unfortunately, the center was closed indefinitely in 2006 because of serious structural problems. I headed instead to nearby Vernal to see the Utah Field House of Natural History.

The star of the museum greeted me in the museum rotunda, a 90-foot-long diplodocus skeleton. Standing under the gargantuan frame, craning my neck to look up into its rib cage, I got an idea of what it must feel like to be a Chihuahua in a human world.

The field house was designed primarily as an educational center, with several hands-on exhibits for kids. My tour started with a 15-minute movie that explained the history of the Morrison Formation -- the fossil-rich sedimentary layer that stretches 600,000 square miles from Canada to the American West. Outside the building, I strolled along the “Dinosaur Garden,” while 14 life-size replica monsters, including a T. rex, a stegosaurus and a woolly mammoth, eyed me ominously.

The drive: If you have an extra two or three hours, drive about seven miles outside of Vernal along U.S. 191 to Red Fleet State Park, where you can see dinosaur tracks on the northern shore of the lake. These prints, at the end of a 1.5-mile hike, are not as distinct as the impressions on Copper Ridge but are still impressive.

The vitals: Open 9 a.m. to 5 p.m. daily, except holidays. Admission: $6 for adults, $3 for seniors and children. 496 E. Main St., Vernal; (435) 789-3799 or go to www.blm.gov/ut/st/en/fo/price/recreation/quarry.html

BYU Earth Science Museum

It’s easy to overlook Brigham Young University’s Earth Science Museum, across the street from the university’s football stadium. It’s a corrugated metal building that looks more like a warehouse than a museum.

Although the building acts primarily as a research center -- you can watch students behind a glass partition clean bones the size of sousaphones -- the dinosaur displays are magnificent.

Among the highlights are the skeleton of an menacing torvosaurus, a predator with teeth that hang like stalactites. Most of the bones used in museum skeletons are reproductions because real fossils are too fragile to mount. Authentic fossils are kept under glass. One such example is the genuine 4-foot-tall leg bone of a Utahraptor, the nasty larger cousin of the turkey-sized velociraptor.

But then my eyes were drawn to the skull of a T. rex, set low enough on a mount that I could stick my head between the jaws and imagine being a chew toy for the king of the dinosaurs.

The drive: Driving through the Manti-La Sal National Forest along U.S. 6, I was struck by the dapples of bright fall colors among the pine and fir forest in early September. Fiery yellows and vivid reds from oak, maple and aspen trees caught my eye.

The vitals: Open 9 a.m. to 5 p.m. Monday through Friday. Admission is free, but donations are accepted. 1683 N. Canyon Road, Provo; (801) 422-3680 or go to https://cpms.byu.edu/ESM/information.html

North American Museum of Ancient Life at Thanksgiving Point

Nearly every paleontologist I spoke to before venturing into Utah talked about the North American Museum of Ancient Life at Thanksgiving Point as if it were the Taj Mahal of dinosaur museums.

They weren’t exaggerating. This place brings the dinosaur era to life, complete with spooky lighting and eerie sound effects.

The 86,000-square-foot museum -- the world’s largest collection of life-size dinosaur skeleton casts -- is part of a larger, 700-acre commercial development that includes gardens, golf greens, shops, an animal park, a farmers market and more.

Every other Utah museum I visited survived on donations, admission fees and contributions from cash-strapped state or local governments, but the Thanksgiving Point museum benefited from the backing of Alan Ashton, co-founder of WordPerfect, named in 1995 one of Forbes magazine’s 400 wealthiest Americans. The $20-million museum was built in 2000 and still has that new-building smell.

Entering the rotunda, I came face-to-toe with a two-story-tall torvosaurus -- the museum’s snarling doorman. This creature would be the star attraction at any other museum, but at Thanksgiving Point it’s just the opening act.

The museum, home to more than 60 complete dinosaur skeletons, is divided into four sections, each representing a period of Earth’s history. I sped through the Precambrian age, when the Earth was a bubbling caldron of single-cell critters, to spend more time in the Triassic, Jurassic and Cretaceous periods.

In the dinosaur exhibit halls, the sound of prehistoric birds echoed from hidden speakers. The dim lights made the towering skeletons look ominous.

Here, size is relative. I’m an average-size man, but at the feet of two battling tyrannosaurus casts, I’m a runt. Then again, the T. rex looks like a pipsqueak next to the supersaurus, one of the world’s largest dinosaurs, stretching 110 feet from head to tail. The neck of the supersaurus is so long it extends into the next exhibit hall.

After four straight days immersed in the world of dinosaurs, I was starting to suffer from Mesozoic overload. Still, I couldn’t pass up the XANGO Mammoth Screen 3D Theatre inside the museum.

I donned a pair of plastic 3-D glasses and watched a computer-generated giganotosaur, a predator even bigger than the T. rex, battle the titanic argentinosaur in scenes complete with oozing blood and sound effects that rattled my fillings.

The film briefly tried to explain the demise of the dinosaurs but by then I already knew the truth: Dinosaurs are not extinct. They’ve just moved to Utah.

The drive: From Provo to Lehi, I followed I-15 past industrial warehouses and strip malls, the kind of developments that refuse to go extinct.

The vitals: Open 10 a.m. to 8 p.m. Mondays through Saturdays, except Thanksgiving and Christmas. Admission: $10 for adults; $8 for children. Admission plus a 3-D movie: $15 for adults; $12 for children. 3003 N. Thanksgiving Way, Lehi. (888) 672-6040 or go to www.thanksgivingpoint.com.

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hugo.martin@latimes.com