Explore the Mysterious Underground
Western Colorado contains hundreds of undeveloped caves on public and private land. Explore these caves with others who care about protecting caves and learning more about the remarkable underground world.
National Speleological Society Caving
Join forces with America's largest and most prestigious organization of cavers, cave scientists and cave conservationists.
Welcome to the Colorado Western Slope Grotto
Based in Glenwood Springs and Rifle, the Colorado Western Slope Grotto is close to the state's finest cave regions.
Learn About the Region's Unique Caves and Karst Features
As a member of the Colorado Western Slope Grotto and the National Speleological Society, you'll learn about and visit interesting caves and karst features in Colorado and the Rocky Mountain West.
Help Expand Knowledge through Discovery
Cavers with the National Speleological Society explore, document, study and protect caves. Contribute to the growing knowledge of Colorado's caves through participation.
Adventure is Underground
Colorado Grotto founder and prolific author Dr. William R. Halliday once famously said, "Adventure is Underground." For Colorado cavers, the promise of underground wonders that Dr. Halliday and his founders sought in the early 1950s has at last been fulfilled through remarkable spelean discoveries throughout Colorado. The area near Glenwood Springs and Rifle, home to the National Speleological Society's Colorado Western Slope Grotto, is particularly rich with cave and karst features. Here, you'll find some of the state's most impressive and longest known caves. There's promise, too, of much more to yet be discovered.
Learn about our grotto, and how you can get involved.
Keep up on CWSG and other events throughout the Rocky Mountain Region.
Join the Colorado Western Slope Grotto
By joining as a member of the Colorado Western Slope Grotto, you'll have the opportunity to work with other cavers to discover the wonders of the region. You'll be connected with the Colorado caving community and meet and join with cavers, scientists and conservationists from Denver, Colorado Springs, Fort Collins, Boulder and other Colorado cities. And, as a member of the National Speleological Society, you'll be introduced to a large national network of cavers.