We went on the Kawau Water Taxis Mansion House Cruise, which provides more than enough time on the water. You leave Sandspit at 10.30 and get to Mansion House Bay around 11.30am.
The trip lands at Mansion House, which is spectacular, even more so considering its history and its importance to NZ. We managed to look around the house, have a picnic lunch, and complete the walk to the Copper Mine Lookout returning via Redwoods track and Two House Bay in the time available. Neither track very challenging (although the last part from Two House Bay to Mansion is a little steep) and our 7 year old managed just fine.
We'd recommend just the Mansion House Cruise if you are physically capable of walking the tracks. Take a picnic and lots of water. If not, the Mail Run, which has less time on the ground, may be more appropriate.
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