Caption on verso: "The Pioneer / A sudden storm in a treacherous canyon --- He died with his boots on. And on the edge of the Snake River Canyon, two desert ranchers of Idaho erected this crude cross to honor the pioneer of the air mail."
[Grave marker for William E. Sanborn], [1987-09-22-B_image_037]. Museum of Flight Digital Collections, accessed 16/04/2026, https://digitalcollections.museumofflight.org/nodes/view/29210