Unexpected Dinosaur Fossil Unearthed Beneath Denver Museum Parking Lot

In January 2025, the Denver Museum of Nature & Science (DMNS) made an unexpected discovery beneath its own parking lot: a fossilized dinosaur vertebra unearthed during a geothermal energy drilling project. This vertebra, dating back approximately 67.5 million years to the Late Cretaceous period, is believed to belong to a small herbivorous dinosaur, possibly a Thescelosaurus or Edmontosaurus. The find represents the deepest and oldest dinosaur fossil discovered within Denver's city limits.

The fossil was encountered during a borehole drilling that reached over 750 feet deep, part of a study assessing the potential for geothermal heating at the museum. The discovery is considered exceptionally rare, with similar occurrences reported only twice worldwide. The fossil's shape suggests it belonged to a duck-billed dinosaur or Thescelosaurus. Fossilized vegetation found alongside the bone indicates the area was once a swampy environment.

The DMNS is a prominent institution dedicated to educating the public about the natural world. It houses extensive collections in paleontology, anthropology, geology, and zoology. The museum is known for its dinosaur exhibits, including full-size skeletons that attract visitors of all ages.

In 2024, the museum received a $250,000 grant from Governor Jared Polis's Geothermal Energy Grant Program and the Colorado Energy Office. This funding was part of a $7.7 million statewide initiative to reduce greenhouse gas emissions and transition to clean energy. The museum's geothermal study aimed to explore strategies for designing a system to meet its long-term heating, air-conditioning, and hot water needs. The transition to geothermal energy is expected to save the museum money, reduce greenhouse gas emissions, and increase energy cost predictability.

Thescelosaurus was a small, herbivorous dinosaur from the Late Cretaceous period, known for its robust limbs and selective feeding habits. It lived in what is now North America and was among the last non-avian dinosaurs before the Cretaceous-Paleogene extinction event.

Edmontosaurus was a hadrosaurid, or duck-billed dinosaur, also from the Late Cretaceous. It was widely distributed across western North America, ranging from Colorado to Alaska. Edmontosaurus was a herbivore capable of moving on both two and four legs and is known from several bone beds, suggesting it lived in groups and may have been migratory.

The fossil is now showcased in the museum's "Discovering Teen Rex" exhibition. This exhibition features a wide array of dinosaur fossils, including Triceratops and Edmontosaurus specimens from the museum's collection. Visitors can observe paleontologists as they clean, preserve, and study rare fossils, offering a unique opportunity to witness scientific research in action.

James Hagadorn, the museum's curator of geology, highlighted the rarity of the find, stating, "Finding a dinosaur bone in a core is like hitting a hole in one from the moon." Patrick O'Connor, curator of vertebrate paleontology at the museum, noted that this discovery is the museum's deepest and oldest fossil find to date.

This discovery underscores the potential for significant paleontological finds even in urban settings, suggesting that other metropolitan areas might harbor similar hidden treasures. It also highlights the value of integrating scientific research with infrastructure projects, as the fossil was uncovered during a geothermal energy study. The find provides new insights into the prehistoric environment of the Denver area, indicating it was once a swampy habitat. Additionally, the exhibition of the fossil enhances public engagement and education, fostering a deeper appreciation for paleontology and natural history.

The Denver Museum of Nature & Science's unexpected discovery beneath its own parking lot serves as a reminder of the hidden history beneath our feet and the continuous potential for scientific discovery, even in the most familiar of places.