Castle Butte (usnm)
Rockhounding site in Montana, Montana · Fossils
Castle Butte (usnm) is a fossil rockhounding site near Montana, MT. Fee varies. Best season: Spring through fall.
Typical season: Spring through fall
Key facts
Structured details for trip planning — verify access and fees with the land manager before you visit.
- Specimen type
- Fossil
- Primary specimens
- Fossils
- Fee status
- Fee varies
- Nearest town
- Montana
- State
- Montana
- Coordinates
- 46.37583, -106.80306
- Best season
- Spring through fall; confirm seasonal road access
- Access difficulty
- Moderate; remote roads possible
- Camping
- Dispersed camping may be available nearby; verify land rules
- Activities
- Rock and mineral collecting
- Facilities
- Montana regional services
- Last updated
- July 5, 2026
What to pack for Castle Butte (usnm)
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The experience
- Best time to visitSpring through fall; confirm seasonal road access
- AccessModerate; remote roads possible
- FacilitiesMontana regional services
- Camping nearbyDispersed camping may be available nearby; verify land rules
Map & location
Sources & updates
Spotted outdated access, fees, or safety info? Send a correction with the page URL — we review every submission.
Safety notice: Field and weather conditions change with weather, season, and field conditions. Verify current conditions with local land managers before you go. Collect at your own risk — there are rarely rangers or land managers at these sites.