Fossil Atlas answer
T. rex fossils are best documented from western North America, especially latest Cretaceous rocks such as the Hell Creek Formation of Montana, the Dakotas, and Wyoming. Fossil Atlas maps selected records so you can separate modern discovery evidence from broader range claims.
Primary source
The Hell Creek Formation is the core T. rex-producing rock unit represented in Fossil Atlas. Stretching across eastern Montana, western North Dakota, northwestern South Dakota, and northeastern Wyoming, Hell Creek preserves river-deposited sandstones and floodplain mudstones from the final million years of the Cretaceous. The formation has yielded famous named specimens, partial skeletons, isolated bones, and teeth.
Famous specimens
Sue, Stan, and the Wankel T. rex are useful examples of why locality and collection history matter. They show how a fossil record becomes more valuable when its formation, discovery area, repository, and specimen identity are preserved together. This page keeps those famous names as context, while the linked Fossil Atlas map stays focused on modern discovery records from the site dataset.
Fossil Atlas coverage
The Fossil Atlas T. rex profile maps selected occurrence records from the current site dataset. Each pin links to fossil-record context with source labels, confidence notes, and formation data where available. The map represents a curated selection, not an exhaustive catalogue of every known T. rex find.
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FAQ
The first recognized Tyrannosaurus rex specimen was discovered by the legendary fossil hunter Barnum Brown in 1902 in the Hell Creek Formation near Jordan, Montana. Brown was working for the American Museum of Natural History under the direction of Henry Fairfield Osborn, who formally named T. rex in 1905. That first specimen (AMNH 973) was a partial skeleton. Brown found a more complete second specimen in 1908, also in Montana, which became the centerpiece of the AMNH's dinosaur hall for decades.
Hell Creek is the main T. rex-bearing formation represented on Fossil Atlas, with exposures across Montana, North Dakota, South Dakota, and Wyoming. T. rex fossils have also been reported from the Lance Formation of Wyoming, the Scollard Formation of Alberta, Canada, and the Frenchman Formation of Saskatchewan. Some fragmentary tyrannosaurid material from the southwestern United States has been attributed to T. rex or closely related species, though those attributions are debated.
Sue is one of the most complete and best-known T. rex specimens. It was found in 1990 by fossil hunter Sue Hendrickson near Faith, South Dakota, in Hell Creek Formation rocks. The specimen is now housed at the Field Museum of Natural History in Chicago. Fossil Atlas treats named specimens like Sue as useful context, while its own maps focus on selected occurrence records rather than a complete named-specimen catalogue.
Yes. New T. rex specimens continue to be discovered regularly, especially in the Hell Creek Formation of Montana and the Dakotas. Advances in fossil preparation, CT scanning, and geochemical analysis mean each new specimen can reveal previously unknown aspects of T. rex biology — from growth rates and biomechanics to possible evidence of soft tissue preservation. Over 50 T. rex specimens are now known, ranging from isolated bones to nearly complete skeletons, making T. rex one of the best-sampled large theropods in the fossil record.
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Sources
Source links show where Fossil Atlas gets record and curation context. They do not make this page an exhaustive scientific bibliography.
Caveat
The formation list above reflects well-established T. rex-producing geological units. Fragmentary tyrannosaurid material from the southwestern United States is debated and may represent T. rex or closely related species. The count of over 50 specimens includes specimens of varying completeness.
Fossil maps on linked pages show modern discovery locations for selected records. These are not ancient habitat or range maps.