During our visit to Devonport, a lovely historical village on the North Shore of Auckland we went to North Head which contains an extensive collection of military tunnels which are open for exploration. The scenic views from this area are beautiful and the history is amazing. A link is attached for further reading if interested the history dates back to 1870's when they started using North Head for heavy armaments against a possible Russian invasion and continued to devleop throughout the years particularly during World war II http://www.devonport.co.nz/north_head.htm for further information.