Cornel Wilde was recovering from surgery for a detached retina during filming, and sometimes had difficulty seeing, although he insisted on doing all of his own stunts.
Les Martin (Cornel Wilde) is handed a flat top can of Van Merritt beer by Janice's father, a rare beer with a short production span.
The plane the smugglers used was a 1929 Curtiss-Wright Travel Air A-6000-A, #N377M.
The seaplane used to search the canyon is a Grumman G-21 Goose.
Opening credits: The characters and incidents portrayed and the names used herein are fictitious, and any similarity to the name, character or history of any person is entirely accidental and unintentional.