We have over 400 parks and field offices nationwide, and she hasn't even been to half of them.
These lists are useful because they highlight problems within the park system for the public.
The role of the park service is to preserve history. New units are created yearly, which tend to be historic places that educate people about important events.
The Burial Ground Monument is the latest National Park unit created to commemorate an historical tragedy.
The park service has had a just-say-no policy.