On the trail of giants in Utah's own Jurassic Park

As I hiked to a flat stretch of sandstone near Moab, Utah, I saw what I came for: Dinosaur tracks.

I ran my fingers along the curve of the claw and pressed my palm inside the hubcap-size impression. It was a strange feeling to occupy the same spot as an SUV-sized lizard.

When the giant meat eater, probably an allosaurus, walked across this spot about 150 million years ago, the landscape was a tropical environment on the shores of an 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 creature.

A happy geological fluke has made Utah one of the world's best spots to hunt for dinosaurs. Throughout the rest of the U.S., this fossil-rich layer of sedimentary rock is buried under prairies and forests. But in the badlands of Utah, the stratum rests near the surface, even along hiking trails like this one.

Thanks to improved technology and 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 duck-billed herbivore, a new horned quadruped, plus evidence that some dinosaurs fished.

I consulted Utah's top paleontologists on the best way to make a four-day road trip to see the state's dinosaur exhibits. Here are my favorite stops:

St. George Dinosaur Discovery Center, Johnson Farm

Eight years ago, Sheldon Johnson, a retired optometrist, was prepping land for resale when he spotted something in the soil. 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.

Johnson notified paleontologists and city officials in St. George, in southwest Utah and about a two-hour drive from Las Vegas, who later built a museum around the 200-million-year-old impressions. Among the exhibits is the world's largest slab of stone containing dinosaur prints, weighing more than 26 tons.

From bones, paleontologists learn about the size, anatomy and diet of dinosaurs. From track prints, experts get clues on how they sat, ran, turned and hunted. Andrew C. Milner, paleontologist for the town of St. George, believes scratch marks on several slabs suggest some dinosaurs swam in the shallows pursuing fish.

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

Mill Canyon Dinosaur Trail and Copper Ridge Dinosaur Trackway

From the recreation hub of Moab in southeast Utah, I drove north to a hiking trail on U.S. Bureau of Land Management territory in Mill Canyon.

There, exposed to the elements were dozens of dinosaur bones, black, gray and grainy, like wood. The disjointed bones jutting out of a sandstone shelf were the vertebrae of a 20-ton camasaurus. A diamond-shape bone embedded in rock was the femur of an allosaurus, a smaller cousin of Tyrannosaurus rex.

The BLM installs interpretive markers on sites but doesn't post road signs for fear that too many visitors will "love the fossils to death," according to BLM officials. 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 from a 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 an apatosaurus, seem to make a sharp right turn, a move that paleontologists say is unusual.

The vitals: Both track sites are open year-round. For Mill Canyon, take U.S. Highway 191 north from Moab for 13 miles, turn left on Mill Canyon Road after mile marker 141. After reaching a "T" in the dirt road, turn left and look for a gravel parking lot and interpretive sign. For Copper Ridge, drive past mile marker 148, along U.S. 191, about 23 miles north of Moab, turn right on the next dirt road and follow the signs for 2 miles to a gravel parking lot.

For information, contact the BLM's Moab Field Office, 82 E. Dogwood, Moab; 435-259-2100 or www.blm.gov/ut / (search for "Canyon Country paleontology").

Cleveland-Lloyd Dinosaur Quarry

At this site in the 1930s, about 30 miles south of the town of Price, paleontologists uncovered the densest collection of fossils in the world — more than 12,000 bones in one-quarter of an acre.

It remains a mystery as to why there were so many bones in one spot, most from juvenile and adolescent carnivores such as the allosaurus. Fewer than 30 percent were herbivores, and paleontologists have been unable to find an intact skull.

Some suggest the land was a bog that trapped herbivores and attracted predators. But that doesn't explain a preponderance of predator bones.

The vitals: Closed in winter; will reopen in mid March. To reach the quarry, drive north of Moab toward Price and take Utah Highway 10 south to the Cleveland/Elmo turnoff, then follow the signs. The last 12 miles are unpaved. For information, call the BLM office at Price, 435-636-3600 or 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 one of the state's premier fossil viewing sites. Unfortunately, the center was closed indefinitely in 2006. I headed instead to nearby Vernal to see the Utah Field House of Natural History State Park.

The star of the museum is a 90-foot-long diplodocus skeleton. The field house was designed as an educational center, with hands-on exhibits for kids. A 15-minute movie explained the Morrison Formation — the fossil-rich sedimentary layer that stretches 600,000 square miles from Canada to the American West.

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 www.stateparks.utah.gov/.

BYU Earth Science Museum

Brigham Young University Earth Science Museum in Provo (just south of Salt Lake City) is a research center — students behind a glass partition clean bones and the dinosaur displays are magnificent.

Highlights include the skeleton of a torvosaurus, a predator with teeth that hang like stalactites. Bones of museum skeletons are reproductions because fossils are too fragile to mount. One fossil under glass is the 4-foot-tall leg bone of a Utahraptor, the nasty larger cousin of the turkey-sized velociraptor.

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 http://cpms.byu.edu/ESM/information.html.

North American Museum of Ancient Life This museum, in the suburban community of Lehi north of Provo, 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 700-acre commercial development called Thanksgiving Point that includes gardens, golf greens, shops, animal park, farmers market and more.

The museum has benefited from the backing of Alan Ashton, co-founder of WordPerfect, one of Forbes magazine's 400 wealthiest Americans in 1995. The $20-million museum was built in 2000.

A two-story-tall torvosaurus is the museum's doorman. It's just the opening act. Home to more than 60 complete dinosaur skeletons, the museum is divided into four sections, each representing a period of Earth's history: the Precambrian age, when Earth was a bubbling caldron of single-cell critters, and the Triassic, Jurassic and Cretaceous periods. The sounds of prehistoric birds echo from hidden speakers.

The supersaurus, one of the world's largest dinosaurs, stretches 110 feet from head to tail. The neck of the supersaurus is so long it extends into the next exhibit hall.

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