Great Barrier Island
Great Barrier Island is the largest of the Hauraki Gulf islands. It is in the Auckland Region, just off the coast of the Coromandel Peninsula.
By ferry from Auckland. Or by a plane, at Great Barrier Airlines. The planes leave from many different areas, including Auckland, Northshore, and Whanagari.
Mount Hobson, Hirakimata is Great Barrier's highest point which is 621 metres. On a clear day it offers spectacular views of the Mercury Islands to the Poor Knights, and the Hauraki Gulf.
The Barrier is more expensive than other areas of New Zealand, especially when it comes to food and petrol. If you're self-catering it'd be wise to bring some food from the mainland.
You wouldn't come for the shopping but the usual souvenirs (postcards, key chains, etc.) are available at most of the shops
There is internet access at the Claris Texas Cafe and a handful of other places, but Great Barrier Island is the type of place to get away from computers and the like. Mobile phone reception is very limited.
Take the ferry back to Auckland or sail your own boat.