Dinosaur fossils found under Utah parking lot in first dig at monument since 1924

3,000 Pounds of Diplodocus Pulled From Beneath Asphalt

Construction crews repaving a parking lot at Dinosaur National Monument made an unexpected find on September 16, 2025.

After removing old asphalt near the Quarry Exhibit Hall, workers spotted fossilized bones just inches below the surface.

What followed was the first fossil excavation at this famous quarry since 1924.

First Dig in Over a Century

The discovery triggered the first fossil excavation at this location since the original excavations ended in 1924.

For more than a century, the ground beneath the parking lot sat untouched while millions of visitors walked overhead to see the nearby Wall of Bones exhibit.

Historic excavations were led by the Carnegie Museum from 1909 to 1922, the Smithsonian National Museum of Natural History in 1923, and the University of Utah in 1924.

After that, nobody dug here again until a routine road project changed everything.

Crews Extract 3,000 Pounds of Fossils

Roughly 3,000 pounds of fossils and rock were removed during the excavation between mid-September and mid-October.

Park staff, a Utah Conservation Corps crew, volunteers, and on-site construction crews assisted in the fossil removal.

Hunt-Foster described the sandstone as extremely hard, requiring significant effort to free the bones. The parking lot construction and road improvement project was completed after the excavation concluded.

The Bones Belong to a Diplodocus

The discovery turned out to be 14 tail vertebrae, a humerus, a radius, an ulna, a tibia, a fibula, and a few toes.

Scientists believe the fossils belong to a Diplodocus, a long-necked sauropod common in this ancient bone bed.

So far, they have collected about 20 feet of dinosaur. The animal would have been massive in life, but this specimen represents only a portion of a full skeleton.

The Parking Lot Hid Old Excavation Debris

The parking lot itself was built on the tailings and backfill from the original excavations during the early 20th century.

As monitors watched construction, they found small fossils that had been tossed aside during those historic digs.

As the construction site neared a 12-foot-thick sandstone wall, the same geologic feature that preserved the Quarry Wall bones, Hunt-Foster and her team started keeping a very close eye on things.

Earl Douglass Found the First Bones in 1909

In 1909, Earl Douglass found eight dinosaur tailbones protruding from a sandstone hill in the Utah desert.

The Carnegie Museum paleontologist had been searching for specimens to display in Pittsburgh. The bones he found turned out to be part of the most complete Apatosaurus skeleton ever discovered.

His find launched one of the most productive dinosaur quarries in North American history and led to the monument’s creation in 1915.

The Site Shipped 700,000 Pounds East

From 1909 to 1923, Douglass and his crews collected more than 350 tons of fossils from that site alone.

The bones traveled by train to museums across the country, including the Carnegie Museum of Natural History, the Smithsonian, and others.

Sauropod skeletons from the quarry are displayed at the Smithsonian Museum of Natural History, Royal Ontario Museum, Carnegie Museum of Natural History, American Museum of Natural History, and Denver Museum of Nature and Science.

The Wall of Bones Holds 1,500 Fossils

The Quarry Exhibit Hall allows visitors to view a wall of approximately 1,500 dinosaur bones.

The building sits over a preserved section of the original quarry where fossils remain embedded in rock tilted at a steep angle.

The bones are just as nature arranged them more than 150 million years ago, deposited by an ancient stream.

Visitors can see remains from 10 different dinosaur species without a pane of glass between them and the fossils.

Ancient Rivers Created This Graveyard

The Morrison Formation is a distinctive sequence of Upper Jurassic sedimentary rock found in the western United States which has been the most fertile source of dinosaur fossils in North America.

Most of the fossils occur in the green siltstone beds and lower sandstones, relics of the rivers and floodplains of the Jurassic period.

Dinosaurs that died near these waterways were buried in sand and mud, their bones preserved for 150 million years until erosion and excavation brought them back to light.

Visitors Can Watch Scientists Clean Fossils

The remains are currently housed at the Utah Field House of Natural History State Park Museum in Vernal, Utah, where they are being cleaned and studied.

The work can be viewed in the museum’s fossil preparation lab.

Fossils from the excavation are also on display at the Quarry Exhibit Hall and the Utah Field House of Natural History State Park Museum.

The preparation process can take months as technicians carefully remove rock from bone.

More Bones Wait Underground

Though Hunt-Foster can tell that the animal stretches deeper into the hillside, they will have to wait until spring, after the threat of snow has passed, to continue excavations.

The 20 feet of Diplodocus already recovered represents only a fraction of what a full skeleton would contain.

For now, scientists are focused on cleaning and studying what they have, while the rest of this 150-million-year-old giant remains buried where it has been since the Jurassic.

Explore the Dinosaur Quarry in Utah

Dinosaur National Monument straddles the Utah-Colorado border near Vernal, with the famous Quarry Exhibit Hall. The Quarry Visitor Center is located 7 miles north of Jensen, Utah, off Highway 149.

During summer months, shuttle buses transport visitors from the visitor center to the exhibit hall. You can touch real fossils along the 2.4-mile Fossil Discovery Trail that connects the two buildings.

The monument charges $25 per vehicle for a seven-day pass. Check current hours and shuttle schedules before visiting, as they change seasonally.

This article was created with AI assistance and human editing.

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