((a)) ** .—** In furtherance of section 100101(a), Congress finds that the preservation and conservation of System unit resources and values requires that public accommodations, facilities, and services that have to be provided within those System units should be provided only under carefully controlled safeguards against unregulated and indiscriminate use, so that—

((1)) visitation will not unduly impair those resources and values; and

((2)) development of public accommodations, facilities, and services within System units can best be limited to locations that are consistent to the highest practicable degree with the preservation and conservation of the resources and values of the System units.

((b)) ** .—** It is the policy of Congress that the development of public accommodations, facilities, and services in System units shall be limited to accommodations, facilities, and services that—

((1)) are necessary and appropriate for public use and enjoyment of the System unit in which they are located; and

((2)) are consistent to the highest practicable degree with the preservation and conservation of the resources and values of the System unit.