1 Fed. Reg. 668, 674, National Park Service Rules and Regulations (1936)

8. Firearms, etc.--Firarms, explosives, traps, seines, and nets are prohibited Within the parks and monuments; except upon written permission of the superintendent or custodian. Visitors entering or, traveling, through the parks and monuments to places, beyond shall, at entrance, report and, if required to do so, surrender all such objects in their possession to the first park or monument officer, and, in proper cases, may obtain his written permission to carry them through the park or monument sealed. Failure to obtain such written permission shall be deemed a violation of this regulation. The Government assumes no responsibility for the loss of, or damage to, any such objects so surrendered to any park or monument officer, nor are park or monument officers authorized to accept the responsibility or custody of any other property for the convenience of the visitors.

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