Where to Find Fossils in Montana: 129 Mapped Sites
Montana has 129 documented sites where fossils have been reported, and the best-known are Big Horn Canyon, Horseshoe Hills, and 125 miles NW of Miles City, Montana. Every site is mapped below with GPS coordinates and links to a full report of access and what's been found there. 2 of the 129 sites are on public-access land.
Last updated: — data compiled by the Rockhounding.org Research Team · methodology
Fossils Map: Montana
All 129 fossils sites in Montana. Click a pin for the full site report.
Where Fossils Are Found in Montana
Fossils live in sedimentary rock — limestone, shale, and sandstone. Fresh exposures are everything: roadcuts, creek banks after storms, quarry spoil, and eroding badlands beat weathered outcrop every time.
The richest reported sites in Montana: Big Horn Canyon, Horseshoe Hills, 125 miles NW of Miles City, Montana, AMNH 31-6, Cashen Pocket, AMNH 32-2, Mott Creek.
Local reporting distinguishes Silicified Coral (1 site), Trilobite Fossil (1 site).
Of the 129 sites, 2 are public access. Check each site report for current land status before you go.
All Fossils Sites in Montana
- Big Horn Canyon — Public Access
- Horseshoe Hills — Public Access
- 125 miles NW of Miles City, Montana — Other
- AMNH 31-6, Cashen Pocket — Other
- AMNH 32-2, Mott Creek — Other
- AMNH 3238, Cedar Creek — Other
- AMNH MT-10 Judith River 2 — Other
- Ankylosaur Point — Other
- Big Dry East Quarry — Other
- Big Nose Hill (ROM) — Other
- BL-1083 Blackleaf BL-9 — Other
- Black Eagle (5) — Other
- Black Tail Creek — Other
- Bob's Vacation Site — Other
- Bullwacker Coulee — Other
- Camp-o-saur, MOR TM-003 — Other
- Cashen Ranch (MCZ) — Other
- Castle Butte (USNM) — Other
- Cinnabar Mountain, Park County — Other
- Cloverly (OMNH V62) — Other
- CM Locality 5084 — Other
- Conor's Microsite (CM) — Other
- Constenius Park (Kishenehn) — Other
- D-1: D(B) Hidden Pasture Springs — Other
- Daly's Spur, Beaverhead County — Other
- Douglass Creek Locality 1 — Other
- Dry Fork Coulee — Other
- Eagle Formation VB9611 — Other
- Eagle Formation VB9617 — Other
- Eagle Sandstone — Other
- East Monarch, Unit E — Other
- East of Hyde Post-office — Other
- Egg Gulch, MOR TM-008 — Other
- Engdahl Anthills 1 — Other
- Engdahl Anthills 3 — Other
- Ferguson Ranch (FR) — Other
- Francis Ranch, unit E — Other
- GLAC-PALLOC-0001 — Other
- Golden Val. (MT) pinnid — Other
- Harmonica Hollow — Other
- Hoover Creek, Zone 1, Wolsey shale — Other
- Kerr Butte (UCMP V75196) — Other
- Lead Slug Hill 1 — Other
- Lima region (PROXY) — Other
- Madison Valley — Other
- Medicine Rocks Site 1 — Other
- Missouri Breaks (UC-913) — Other
- Moose Creek Unit E — Other
- MOR 692 (PROXY) — Other
- MOR locality HC-064 — Other
Showing 50 of 129 sites — every site appears on the map above.
How to Identify Fossils
Look for biological structure the rock around it lacks: shell curves and growth lines, the spongy honeycomb interior of bone, leaf veins, ribbed corals, or the segmented symmetry of a trilobite. Fossils usually contrast with their matrix in color or density. Bone that has mineralized feels heavier than fresh bone and often shows a polished brown-black surface.
Not sure what you found? Try our identification guide →Frequently Asked Questions
Where can I find fossils in Montana?
Montana has 129 mapped sites where fossils have been reported. The best-known are Big Horn Canyon, Horseshoe Hills, and 125 miles NW of Miles City, Montana. Each listing on the map above includes GPS coordinates, access type, and what has been found there.
How many fossils sites are mapped in Montana?
We have 129 documented fossils sites in Montana, compiled from community submissions and published locality records and reviewed by the Rockhounding.org Research Team.
Is it legal to collect fossils in Montana?
Casual collecting is generally allowed on BLM and National Forest land for personal, non-commercial use — the standard BLM limit is 25 lbs per day plus one specimen. National parks, monuments, and many state parks prohibit collecting, and private land always requires the owner's permission. Check the site report for each location and verify current land status before you dig.
How do I identify fossil?
Look for biological structure the rock around it lacks: shell curves and growth lines, the spongy honeycomb interior of bone, leaf veins, ribbed corals, or the segmented symmetry of a trilobite. Fossils usually contrast with their matrix in color or density. Bone that has mineralized feels heavier than fresh bone and often shows a polished brown-black surface.
What kinds of fossils are found in Montana?
Reports from Montana distinguish Silicified Coral (1 site), Trilobite Fossil (1 site).
What should I bring to collect fossils?
The basics: a rock hammer, safety glasses, gloves, a bucket or padded bag for specimens, and a GPS app with the coordinates from this page. Add a spray bottle — wetting a stone makes color and banding far easier to judge in the field.
⚠️ Always verify current regulations, weather conditions, and access requirements before visiting any location. Information provided is based on community submissions and may not be current or accurate.
Fossils in Nearby States
Data: Paleobiology Database, community submissions — reviewed and approved by the Rockhounding.org Research Team. Always verify current land status, regulations, and access before visiting any site.