Citadel Rock
Fort Benton, Montana
About Citadel Rock
Citadel Rock is a shonkinite intrusion in north central Montana along the Missouri River. This landmark is accessible by boat only. About one mile downstream from the landmark is the Hole-in-the-Wall boat-camp. The BLM maintains this campground which includes vaulted toilets, three-sided log shelters and fire rings. The camps namesake, a geographic sandstone formation, is aptly named Hole-in-the-Wall.
These are fine-grained igneous rocks, dominated by dark-colored minerals, occur as dikes, sills and stocks injected into fractures in the Cretaceous age sandstones and shales. They range in age from Tertiary to late Cretaceous. They are more resistant to weathering than the enclosing sedimentary rocks, causing them to form promontory features in the surrounding terrain.
Citadel Rock Activities
History
Citadel Rock Amenities
Citadel Rock Reservations
About Citadel Rock
Citadel Rock is a shonkinite intrusion in north central Montana along the Missouri River. This landmark is accessible by boat only. About one mile downstream from the landmark is the Hole-in-the-Wall boat-camp. The BLM maintains this campground which includes vaulted toilets, three-sided log shelters and fire rings. The camps namesake, a geographic sandstone formation, is aptly named Hole-in-the-Wall.
These are fine-grained igneous rocks, dominated by dark-colored minerals, occur as dikes, sills and stocks injected into fractures in the Cretaceous age sandstones and shales. They range in age from Tertiary to late Cretaceous. They are more resistant to weathering than the enclosing sedimentary rocks, causing them to form promontory features in the surrounding terrain.
Citadel Rock Activities
History
Citadel Rock Amenities
Citadel Rock Reservations
About Fort Benton, Montana

Tucked away in a valley on the Missouri River and surrounded by high bluffs, Fort Benton has served as the perfect gateway to Montana adventure for nearly two hundred years. Fur traders established a fort at the site a generation before the Montana gold rushes of the 1860s making Fort Benton the... ...
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