The Dinosaurs Beneath Our Feet

Drive across America and the landscape seems familiar. Cattle graze beneath the enormous skies of Montana. Highways cut through the red-rock country of Utah. Rivers wind through Texas. Forests cover parts of Connecticut and New Jersey. Towns, farms, parking lots, shopping centers, and neighborhoods occupy almost every landscape in between.

But underneath that familiar America is another country entirely. It has no states, no highways, no cities, no national parks. And for more than 160 million years, some of the largest and strangest animals ever to walk the Earth called portions of it home. We know them by names that have become almost mythical... Tyrannosaurus, Triceratops, Stegosaurus, Allosaurus, Diplodocus. They seem like creatures from some distant, lost world. But they aren’t. Their world is directly beneath ours.

America, it turns out, is extraordinarily rich in dinosaur fossils. The spectacular dinosaur-bearing rocks of the West have produced some of the most famous fossils ever discovered, while tracks and bones found elsewhere reveal that dinosaurs weren’t restricted to what we now call Montana, Wyoming, and Utah. They walked across landscapes stretching from Alaska to Texas and from the Rocky Mountain states into parts of the East. And occasionally, they still interrupt construction projects.

In September 2025, workers at Dinosaur National Monument were removing asphalt during improvements near the famous Quarry Exhibit Hall when dinosaur-bearing sandstone was exposed. Construction stopped. Paleontologists arrived. Eventually, roughly 3,000 pounds of fossil-bearing rock were removed. The bones appear to belong to a large, long-necked dinosaur, probably Diplodocus. The location hadn’t been excavated for dinosaur fossils since 1924. Imagine reporting for work expecting to replace pavement. By lunchtime, somebody has essentially announced: “There’s a dinosaur under the parking lot.” Only in America...

Yet the discovery makes considerably more sense once you understand what lies nearby. In 1909, paleontologist Earl Douglass was searching northeastern Utah for dinosaur fossils when he spotted eight connected tail vertebrae belonging to an Apatosaurus protruding from a ridge. He had found something extraordinary. Excavations continued for years, removing hundreds of tons of fossil material. Eventually, instead of excavating everything, part of the original rock face was preserved. Today a building surrounds it. Visitors to Dinosaur National Monument can stand directly before a wall displaying approximately 1,500 exposed dinosaur bones from creatures including Allosaurus, Apatosaurus, Camarasaurus, Diplodocus, and Stegosaurus. It is difficult to imagine a better demonstration of just how thoroughly dinosaurs are embedded in the American landscape.

But Utah hardly has a monopoly. Travel south to New Mexico, and the story becomes stranger. At Ghost Ranch, discoveries beginning in 1947 revealed an extraordinary concentration of Coelophysis, a slender predatory dinosaur from more than 200 million years ago. Scientists have found the remains of at least a thousand individuals there. One dinosaur skeleton is exciting. A thousand begins to look like the guest registry from the world’s worst family reunion. Why so many animals accumulated there remains part of the scientific investigation, but Ghost Ranch gave paleontologists an enormous amount of material to study one of the earliest dinosaurs.

Then there is Montana. If America has a dinosaur state in the popular imagination, Montana has a strong claim to the title. The rocks there preserve creatures from near the end of the dinosaur age, including two names even people who know almost nothing about paleontology recognize: Tyrannosaurus rex and Triceratops. But Montana also gave scientists something arguably more intimate than another enormous skeleton. It gave them families.

At a place now famously known as Egg Mountain, discoveries beginning in the 1970s revealed nests, eggs, and young dinosaurs associated with 'Maiasaura', whose name appropriately means "good mother lizard." The discoveries helped transform how scientists thought about dinosaur reproduction and behavior. These weren’t merely giant reptiles wandering around waiting for an asteroid to arrive. They nested. They laid eggs. They produced young. They gathered in nesting areas. They behaved like animals. That distinction matters because dinosaurs become considerably more interesting when we stop thinking about them as monsters and start thinking about them as living creatures.

And nowhere is that feeling stronger than in a footprint. A bone tells us: a dinosaur died here. A footprint tells us: a dinosaur was here, and then it kept going. Texas preserves some magnificent examples.

At Dinosaur Valley State Park near Glen Rose, Texas, dinosaurs left tracks in soft sediment during the Early Cretaceous. In 1938, paleontologists Roland T. Bird and Barnum Brown investigated remarkable trackways made by enormous long-necked sauropods and meat-eating theropods, all seemingly moving in the same direction. Those sauropod tracks became the first scientifically described tracks of their kind.

Think about what a footprint actually represents: an animal walked across wet ground, lowered one enormous foot, its weight compressed the mud, then it lifted that foot and took another step. Nothing extraordinary was happening. The dinosaur wasn’t dying, it wasn’t being buried, and it certainly wasn’t pondering paleontology. It was simply walking. Yet that completely ordinary moment survived for more than 100 million years.

Texas has yielded body fossils as well. Big Bend National Park contains dinosaur bones and teeth, part of a fossil record documenting a region that looked dramatically different during the Cretaceous than the desert landscape visitors see today.

Colorado and Wyoming provide still more familiar names. Stegosaurus, with its magnificent plates and tail spikes, inhabited the Late Jurassic West. Allosaurus stalked the same ecosystems. Enormous sauropods such as Apatosaurus and Diplodocus moved across floodplains in landscapes preserved today within the famous Morrison Formation. At Utah’s Cleveland-Lloyd Dinosaur Quarry, approximately 10,000 dinosaur bones have been recovered, and roughly 70 percent belong to Allosaurus. Scientists have identified material from at least 46 individuals, although precisely why so many predatory dinosaurs accumulated there remains uncertain. Apparently, even after 150 million years, the crime scene still has unanswered questions.

But dinosaurs weren’t exclusively Westerners. That’s one of the easiest misconceptions to acquire, because western North America possesses enormous exposures of dinosaur-bearing sedimentary rock. The eastern United States has a more fragmented record, but dinosaurs unquestionably lived there, too. New Jersey became enormously important to American paleontology through the discovery of 'Hadrosaurus foulkii' in the nineteenth century. Connecticut and Massachusetts preserve dinosaur footprints. Other eastern states have produced bones or tracks where the appropriate Mesozoic rocks survived. Even Alaska preserves evidence of dinosaurs.

The modern map can fool us. Montana wasn’t Montana. Texas wasn’t Texas. And the United States certainly didn’t exist. At different moments during the Mesozoic, enormous inland seas divided portions of North America. Coastlines shifted. Temperatures changed. Forests grew where today we find grasslands or deserts. Rivers crossed floodplains that eventually became stone.

The America beneath America is therefore not one lost world. It’s many. And our understanding of those worlds continues changing because fossils are still being discovered. Sometimes professional paleontologists deliberately search formations known to contain dinosaurs. Sometimes erosion exposes a bone. Sometimes a rancher notices something unusual. Sometimes someone follows a footprint. And apparently sometimes the National Park Service hires a crew to remove asphalt and the Jurassic period interrupts the construction schedule.

That may be the most wonderful thing about America’s dinosaur story: we haven’t finished finding them. There are undoubtedly fossils still buried beneath hillsides and badlands, protected inside rocks that haven’t yet eroded enough to reveal what they contain. Most will never become spectacular museum skeletons. Some may be a single tooth, a bone fragment, an eggshell, or a footprint. But every piece contains information. Together they allow scientists to reconstruct ecosystems that disappeared tens of millions of years before the first human existed.

And perhaps that is why dinosaur fossils inspire such extraordinary wonder. We usually experience history through things humans left behind: buildings, letters, tools, photographs, battlefields. Dinosaurs demand that we abandon the human scale entirely.

Long before there was a Montana ranch, enormous animals lived and died there. Before there was a Texas riverbed, dinosaurs crossed soft Cretaceous ground. Before Utah had highways, Diplodocus moved across ancient floodplains. Before anyone drew a boundary around Colorado, Stegosaurus walked through a world that would have been utterly unrecognizable to us.

Then that world disappeared. Rock accumulated above it. Mountains rose. Rivers carved valleys. Continents changed. Eventually people arrived. We built farms. We paved roads. We constructed towns. We put parking lots over places where dinosaurs had been buried for more than a hundred million years.

And every so often, erosion, or a shovel, or a construction crew, opens a tiny window through all that time. We peer through it. And something on the other side looks back.

We didn’t discover some distant lost world. We built our world directly on top of it...