Bighorn-Horsethief Resurvey Project

Last Update: December 23, 2021


The Bighorn-Horsethief Cave system is one of the region’s most significant caves. Currently the system has been measured at 14.615 miles ( from past surveys. These surveys were completed in the 70’s and 80’s by various different of grottos and organizations. These past surveys were completed with analog instruments. Unfortunately a significant amount of data from past surveys has been lost. The current maps that are readily available have significant shortcomings of either generalizations or missing passages. The primary goal of this project is to remap the system with modern technology (DistoX2 laser rangefinders) and to create a complete map of the entire system. This will also be a chance to test out new LIDAR technologies.

This project is a fantastic opportunity for cavers of all experience levels to jump in and volunteer, whether you are new to caving and want to check out the longest cave system in Montana, or are an experienced surveyor and wish to keep your skills sharp. We plan to hold various training sessions to cover vertical technique, surveying instrumentation, sketching, conservation, and other caving skills.

Helpful Links

Join the email list to stay informed about upcoming survey trips and other project discussions!

Project Orientation Document – Standards and General Info

Check out the Trello board for current tasks and status.

Our Google Drive folder has all of the project documents and information.

Learn more about how Cave Surveying works! (Don’t know how? We’ll train new folks on their first couple trips out with us!!)

Current Status

Bighorn Caverns

We are currently working with the National Park Service and the Apsáalooke (Crow) Indian Tribe to arrange access for the entirety of the re-survey. The re-mapping effort will not begin in Bighorn until access is approved.

Horsethief Cave

This resurvey project began back in March, 2021. It is currently in the soft opening phase. We expect to host monthly survey trips, open to all members of the grotto, beginning this fall.

Future Project Weekend Dates

Sign ups will be open about a month before the project weekend. The sign up link will be posted on the event listing for each project weekend here:
3/26-3/27/22 (weather dependent)
6/23-6/26/22 (Extra long project weekend!)
11/12-11/13/22 (weather dependent)

Donate to the Project

Project Leaders

The Northern Rocky Mountain Grotto of Montana is sponsoring this effort. Other local grottos are also encouraged to join in on this project.

Project Lead: Will Boekel
Cartography: Hans Bodenhamer
Data Processing and Storage: Jason Ballensky
Materials: Brian Gindling
Permitting: Jason Forberg & Ian Chechet
3D LiDAR Scanning: David Gianforte