Fort Takapuna, used by the New Zealand Defence Forces for over a century, offers a glimpse of New Zealand's 19th and 20th Century military history.
Visit North Head Historic Reserve where a self-guided walk leads you through tunnels and other features of the area's past military defences.
Marine reserves are great places to swim, snorkel, dive and boat. Remember that the reserves are 'no take' areas, so fishing or removing marine life is not permitted.
Parks and recreation - all regions
Official Auckland website