New Zealand Department of Conservation: http://www.doc.govt.nz/
See also: National park for other national parks around the world.
... under the age of 18, 8.0% from 18 to 24, 31.0% from 25 to 44, 21.9% from 45 to 64, and 16.9% who are 65 years of age or older. The median age is 39 years. For every ...