- Where
- Ömnögovi Province,
South Gobi, Mongolia - Coordinates
- 44.14° N
103.73° E - Biome
- Gobi desert-steppe;
red sandstone escarpment - The formation
- Djadokhta Formation, Campanian —
75–71 Ma; older work to c. 84 Ma - Status
- On UNESCO's tentative list
since 2019 — not yet inscribed - Best visited
- June–September; roads and
camps close down in winter
Stood at the bottom of a red wall that used to be underwater, or so I am told, and did not believe it for a full minute. Somebody here got blamed for a crime they did not commit, ages ago, and nobody apologised properly for ages more. I have decided to forgive on their behalf. Item: dig for nothing in particular, respectfully.
The short answer
The Flaming Cliffs — Bayanzag in Mongolian, "rich in saxaul" — are a band of red-orange sandstone cliffs in the South Gobi Desert, part of Ömnögovi Province. They are the type locality of the Djadokhta Formation, a Late Cretaceous rock unit whose age remains unsettled in the literature: recent syntheses place it at roughly 75 to 71 million years ago, older treatments extend it back to about 84 million, and Mongolia's own UNESCO tentative-list submission describes the Djadokhta as approximately 80 million years old. All agree it is Campanian; the precision beyond that is not established. Roy Chapman Andrews, leading the American Museum of Natural History's Central Asiatic Expeditions, gave the cliffs their nickname in 1922 for the way the iron-rich rock glows at sunrise and sunset. In July 1923 his team made a discovery that changed paleontology: a nest of eggs, the first anyone had recognised as belonging to a dinosaur. The site remains an active fossil locality today.
Why it's worth knowing
The famous story deserves a second look in two respects. The first is a matter of attribution rather than accuracy: it is often said that Andrews himself discovered the eggs, but his own field notes record otherwise — team member George Olsen reported at lunch that he had found some fossil eggs, and the group went to look. Andrews led the expedition; Olsen made the find.
The second correction is the more interesting one. A theropod skeleton was found near the nest, apparently amid a cluster of eggs assumed to belong to the far more common Protoceratops. Back in New York, AMNH's Henry Fairfield Osborn named the theropod Oviraptor — "egg seizer" — on the theory that it had died raiding a Protoceratops nest. The name stuck for decades. Then, in 1993, a joint AMNH–Mongolian expedition working a different Gobi locality found an egg of the same type with a fossilised embryo curled inside it, and the embryo was not Protoceratops. It was an oviraptorid. Further specimens turned up preserved in a bird-like brooding posture, wings spread over their own nests. The animal blamed for stealing the eggs had, all along, been guarding them.
The field notes
The cliffs are still giving up fossils
Wind continues to strip material from the escarpment, and eroded bone and eggshell fragments turn up at the base of the cliffs most seasons — the rate of that retreat is quoted in various places at a centimetre or two a year, but the figure traces to informal sources rather than any published survey, so this entry does not assert one. What is not in doubt is the law: Mongolia has declared fossils government property since 1924, and enforcement is real. The clearest illustration is recent. In 2012 a Florida-based dealer put a Gobi-sourced Tarbosaurus bataar skeleton up for auction in New York; Mongolian authorities objected, a federal investigation followed, and the dealer pleaded guilty to smuggling charges in December 2012. Fossils forfeited in the case and returned to Mongolia in 2013 and 2014 included three Tarbosaurus skeletons, six Oviraptor skeletons, and a nest of fossilised eggs — the same categories of object this cliff face is still, quietly, producing.
An expedition looking for the wrong thing
Andrews's patron at the American Museum, Henry Fairfield Osborn, financed the Central Asiatic Expeditions chiefly to test his own pet theory that Central Asia, not Africa, was the cradle of human evolution — the "Out of Asia" idea. The expeditions never found the early human ancestors Osborn was hoping for. What they found instead, largely by consequence, was one of the richest dinosaur and early-mammal fossil beds on Earth. Andrews's own account of the work, and his reputation as a rifle-carrying, car-driving adventurer in a lawless stretch of 1920s Central Asia, is often cited as an inspiration for later fictional archaeologist-explorers, though no direct confirmation from any filmmaker is on record, and the claim is repeated here as a widely circulated one rather than an established fact.
Go for the hour the name promises
At midday the cliffs read as ordinary tan-red rock; the "flaming" effect that gave the site its name is a low-angle-light phenomenon, strongest in the hour or so around sunrise and sunset when the iron oxide in the sandstone catches the light directly. Most Gobi itineraries schedule Bayanzag as a late-afternoon stop for exactly this reason. There is no barrier between the viewing rim and the base of the cliffs, and the walk down is unmarked and occasionally steep; guides generally keep visitors to established paths both for footing and to avoid disturbing anything still emerging from the rock.
- Look for a bone shaped like a story someone else already ruined. Correct the story quietly.
- Walk the red wall at the hour it lights up, and say something appropriately impressed.
- Leave every fragment exactly where it lies. (This is apparently the whole rule. I am very good at this rule.)
- Apologise, on principle, to whoever got blamed first and never got to explain.
- Find one shrub tough enough to survive out here and admire it without touching it. (Almost touched it. Recovered.)
A grey sliver of bone or eggshell, still half in the rock. Wind strips a little more from this escarpment every season, and walkers at the base commonly spot fragments the desert has only just finished exposing. Mongolian law has declared every one of them government property since 1924, so the instruction is to look, photograph, and leave it exactly where erosion put it — the same rule that turned a 2012 smuggling case into a federal prosecution and sent three Tarbosaurus skeletons home.
Tally, in the marginI found a little grey sliver poking out of the cliff and did not pick it up, which felt like the single most mature choice I have ever made in my whole unfinished life.
Getting there
Almost all visitors reach Bayanzag by flying from Ulaanbaatar's new international airport (UBN) to Dalanzadgad (DLZ), a flight of about an hour, then continuing roughly 100 kilometres overland by 4WD — a further two hours or so on unpaved desert track — usually as one stop on a multi-day Gobi loop that also takes in Yolyn Am and the Khongoryn Els singing dunes. Independent self-drive access is difficult given the distances and the lack of signage, so nearly everyone books through a licensed operator; multi-day tours range from roughly $500 for a budget camping itinerary to $2,500 or more for a comfort-level trip with private ger camps, and the June-to-August peak books out weeks to a couple of months ahead as camp capacity is limited.
June through September is the reliable travel window; the road is difficult or closed in winter and the Gobi's summer days can exceed 40°C even as nights turn cold, so pack for both extremes rather than one. The practical rule that matters most: anything that looks like bone, shell or fossilised wood stays exactly where you found it. Report a significant find to your guide rather than pocketing it — the difference between a memorable photograph and a genuine legal problem at the airport.
Common questions
What are the Flaming Cliffs?
The Flaming Cliffs, known locally as Bayanzag, are a red sandstone escarpment in Mongolia's Ömnögovi Province and the type locality of the Djadokhta Formation, a Late Cretaceous rock unit of Campanian age, dated in recent syntheses to roughly 75 to 71 million years ago and in older treatments as far back as about 84 million; Mongolia's UNESCO tentative-list submission gives approximately 80 million. Roy Chapman Andrews named them in 1922 for their glow at sunrise and sunset, and his team's Central Asiatic Expeditions made major dinosaur and early-mammal discoveries there through the 1920s.
Who actually found the first dinosaur eggs at Bayanzag?
Roy Chapman Andrews led the 1923 expedition, but his own field notes record that team member George Olsen made the actual discovery, reporting at lunch on 13 July 1923 that he had found fossil eggs. The find was the first nest of eggs anyone had recognised as belonging to a dinosaur, and it made headlines worldwide under Andrews's name as expedition leader.
Why is Oviraptor called the "egg thief" if it didn't steal eggs?
Oviraptor was named in 1924 by AMNH paleontologist Henry Fairfield Osborn, who assumed the theropod skeleton found near a nest of eggs at Bayanzag had died raiding the nest of the far more common Protoceratops. The genus name means "egg seizer" in Latin, reflecting that assumption rather than any confirmed behaviour.
How was Oviraptor's reputation corrected?
In 1993 an AMNH-Mongolian expedition working the Gobi locality of Ukhaa Tolgod, a different site from Bayanzag, found an egg of the same type containing a fossilised oviraptorid embryo, proving the eggs at Bayanzag had belonged to the theropod all along rather than to Protoceratops. Further specimens found preserved in a brooding posture over their own nests confirmed the animal was a parent, not a predator; the specimens that clinched this are formally classified as the closely related genus Citipati, named in 2001.
Can you keep a fossil you find at the Flaming Cliffs?
No. Mongolia has declared dinosaur fossils the property of the state since 1924, and export without permission is a criminal offence. The law is actively enforced: a 2012 case against a Florida fossil dealer who smuggled a Gobi-sourced Tarbosaurus bataar skeleton into the United States ended in a guilty plea and the repatriation of three Tarbosaurus skeletons, six Oviraptor skeletons and a nest of fossilised eggs to Mongolia in 2013 and 2014.
Are the Flaming Cliffs a UNESCO World Heritage Site?
Not yet. Bayanzag and other Gobi fossil localities were added to Mongolia's UNESCO tentative list in 2019 under the nomination "Cretaceous Dinosaur Fossil Sites in the Mongolian Gobi," which is a preliminary step toward possible future inscription rather than World Heritage status itself.
When is the best time to visit the Flaming Cliffs?
June through September is the reliable travel window, since the unpaved approach road is difficult or impassable for much of the winter. For the effect that gives the site its name, aim to be at the cliffs in the hour or so around sunrise or sunset, when low-angle light catches the iron-rich sandstone directly; at midday the same rock reads as ordinary tan-red stone.