260
Members strong
2000
Chartered
7+
States & provinces
$12
Annual dues
Why join
What you get as a member
Twelve dollars a year gets you deep into the Northern Rockies caving community — and its records.
300+ trip reports
A searchable archive of where members have been caving — with photos, maps, and field notes going back years.
Member directory
Find other cavers in your area, contact trip leaders, and plan your next underground weekend.
Small grant program
NRMG funds member projects — from survey equipment to conservation work. Apply anytime.
Bighorn/Horsethief
Join our flagship long-term survey project in Wyoming’s Bighorn Mountains — multiple trips every year.
Who we are
A scattered, stubborn caving community
Chartered in 2000, our purpose is to promote the discovery, exploration, scientific study, and conservation of caves and karst.
Our core is in Montana, but our membership stretches across Idaho, Wyoming, Washington, Utah, Texas, California, and into Canada. We survey, inventory, map, photograph, monitor, and recreate in caves throughout the Northern Rockies — and a fair amount further afield.
The NRMG is a unique club. We’re spread out, but we’ve kept things active and together for over a quarter-century. New members — whether you’re an experienced caver passing through Montana or someone who’s never been underground — are always welcome.
The Bighorn/Horsethief Project
Our flagship long-term survey project, running multiple weekend trips every year plus a week-long summer expedition. Open to NRMG members at all experience levels.
Read project updates →Latest underground
Recent trip reports
A look at where NRMG members have been caving lately — from Lechuguilla to local Montana classics.
Membership · NSS Internal Organization
Join for $12 a year
Trip reports, the member directory, our small-grant program, the grotto library, and project participation. NSS membership encouraged but not required.
What’s coming up
Upcoming events
Latest from the grotto
News & announcements
Looking back