While it serves as a "glorified orientation film" for the Grand Canyon, is largely remembered as a flawed effort that fails to capture the true peril of Powell's journey.
For a modern look at the rugged Utah landscapes where the film was shot, check out this freeride footage: Ten Who Dared
John Beal as Major Powell, Brian Keith as Bill Dunn, and James Drury as Walter Powell. While it serves as a "glorified orientation film"
Critics and audiences from platforms like IMDb and Rotten Tomatoes generally agree on the following points: Brian Keith as Bill Dunn