This is one of only three active geyser areas in the whole world! (The others are Yellowstone NP and Iceland). Activity has declined here in modern times. When I was there, they thought it was due to their extracting geothermal energy. I see that the geysers are still active now however. Definitely worth a visit.

There is a Maori Cultural Center here as well. The Maori are the indigenous inhabitants of the islands.