Cannonball concretions, Grant County

Where: North Dakota · North America · approx. 46.4, -101.4 (vicinity only)

Why this spot: Huge spherical sandstone concretions weathering from Paleocene bluffs along the Cannonball drainage

What turns up: cannonball concretions, sandstone spheres

Access: Permission required.

Bluffs are largely private ranchland; view or collect small pieces only with consent.

Satellite view, historic-map overlays, tide/flow context and field notes are in the app. Exact research detail is part of Pro.