(a) Visitors are prohibited from entering the canyons of Canyon de Chelly National Monument unless accompanied by National Park Service employees or by authorized guides: Provided, however, That the Superintendent may designate, by marking on a map which shall be available for public inspection in the Office of the Superintendent and at other convenient locations within the monument, canyons or portions thereof which may be visited or entered without being so accompanied.

(b) The Superintendent may issue permits to properly qualified persons to act as guides for the purpose of accompanying visitors within the canyons.