A collapsed cave system in Missouri has left behind a roofless canyon that stretches three-quarters of a mile between towering walls, and it has been called the "Little Grand Canyon" for good reason.

03:00, Tue, Jun 23, 2026 Updated: 03:00, Tue, Jun 23, 2026 Archaeologists have uncovered a remarkably preserved prehistoric cave that is helping researchers piece together a crucial chapter in human ...