It is the Purakaunui Falls, in the Catlins.
Initially, we weren't planning to go there since my wife had a bum knee and couldn't walk. But, she wanted to see it so we walked slowly to the falls.
We spent nine days in the South Island, having flown in to Christchurch. Drove down to Dunedin, then Invercargill, and continued to Manapouri (Doubtful Sound) before hitting Queenstown. Back to Christchurch and fly back to Auckland rested some and flew back to HK before going home in Virginia.
Drove over 2200 km in the South Island, and had a grand time, just didn't see all we wanted to.
Christchurch was very sad, just sorry that the earthquake destroyed and damaged so much, and still haven't rebuilt what was destroyed.
Nice! Where is that one on South Island?