Letter from Carl T. Hayden to Louis C. Cramton about potential prosecution of people with mining claims within park boundaries.

Letter from Carl T. Hayden to Alf Dickenson about mine locations within the park.

Letter from Arno B. Cammerer to Carl Hayden regarding the storage of dynamite in Shoski Canyon.

Letter from Carl Hayden to Hugh E. Campbell with an enclosed outline map of the proposed boundaries of Grand Canyon National Park.