From Wikipedia (http://en.wikipedia.org/wiki/Auckland_Domain):

The Auckland Domain is Auckland's oldest park, and at 75 hectares one of the largest in the city.[1] Located in the central suburb of Grafton, the park contains all of the explosion crater and most of the surrounding tuff ring of the Pukekawa volcano.[2]

The park is home to one of Auckland's main tourist attractions, the Auckland War Memorial Museum, which sits prominently on the crater rim (tuff ring). Several sports fields occupy the floor of the crater, circling to the south of the cone, while the rim opposite the Museum hosts the cricket pavilion and Auckland City Hospital. The Wintergarden, with two beautiful glass houses, lie on the north side of the central scoria cone. The fernery has been constructed in an old quarry in part of the cone.The duck ponds lie in the northern sector of the explosion crater, which is breached to the north with a small overflow stream.