Como Bluff
Near Medicine Bow, Wyoming · United States
Type
Historic Bone Wars Locality
Age
Late Jurassic (Morrison Formation), ~150 mya
Established
Discovered 1877 (Bone Wars era)
Best time
May through September for dry ranch roads
- ◆Epicenter of the Cope–Marsh Bone Wars
- ◆Allosaurus, Apatosaurus, Diplodocus, Stegosaurus, Camarasaurus
- ◆Discovered during Union Pacific Railroad construction
- ◆Morrison Formation type area for classic Jurassic dinosaurs
Photos
Overview
Como Bluff is where the legendary rivalry between paleontologists Edward Drinker Cope and Othniel Charles Marsh reached its fever pitch. Railroad workers cutting through the ridge for the Union Pacific in 1877 noticed fossil bones eroding from the cuts, and both men sent teams to excavate frantically — sometimes dynamiting specimens to deny them to the rival. The quarries here produced some of the most complete Jurassic dinosaur skeletons ever found and helped establish the Morrison Formation as the classic dinosaur-bearing rock unit.
Geology
Como Bluff exposes the Morrison Formation in a series of ridges and cuts near Medicine Bow. The bone-bearing layers are fluvial sandstones and mudstones deposited by Jurassic rivers. Rapid burial in channel and overbank settings produced both isolated bones and articulated partial skeletons of large sauropods and theropods.
What You See
Today Como Bluff is largely on private ranch land with limited public access. The historic quarry cuts are visible from certain roads, and interpretive signage marks the general area. The best specimens are in museums — the Smithsonian, Yale Peabody, and AMNH all hold Como Bluff material.
Famous Finds
Como Bluff yielded the first nearly complete Allosaurus skeletons, important Apatosaurus and Diplodocus material, Stegosaurus specimens, and Camarasaurus — essentially the cast of characters that defined the Jurassic dinosaur hall in every major museum.
Visiting
Public access is limited. Drive the county roads near Medicine Bow for views of the bluff and historical markers. Contact local museums or the University of Wyoming Geological Museum in Laramie for context before visiting.
Best time to visit
May through September for dry ranch roads. The bluff is exposed prairie — wind and sun are intense in summer; bring water.
Getting there
From Laramie, Wyoming: ~1 hour south on I-80 to Medicine Bow, then county roads east toward Como Bluff. From Rawlins: ~45 minutes north. No formal visitor center on-site.
Map
Near Medicine Bow, Wyoming — approximate location only. Exact fossil localities are not published to protect sites from looting.
Market & Provenance
Como Bluff itself is not a commercial source today. Morrison Formation fossils sold legitimately must document private-land collection in Wyoming or neighboring states — never claim 'Como Bluff' without verifiable chain of custody back to legal private land.
Collecting & Legality
Most of Como Bluff is private ranch land — you need landowner permission for any activity. Federal rules apply on adjacent public land: vertebrate fossils cannot be collected for commercial sale. This historic site is protected by its reputation; looting damages scientific context.
FAQ
What were the Bone Wars?
A fierce 1870s–1890s rivalry between Cope and Marsh who raced to name and publish new dinosaurs, sometimes using destructive tactics at shared quarries like Como Bluff.
Can I dig here?
The bluff is mostly private ranch land. You need explicit landowner permission; never assume access.
Where are the famous skeletons?
Major museums worldwide — Yale, Smithsonian, AMNH, and others hold Como Bluff specimens collected during the Bone Wars.