Blenheim is the most populous town in the region of Marlborough, in the north east of the South Island of New Zealand. It has an estimated urban population of 30,500. The surrounding Marlborough wine region is well known as the centre of the New Zealand wine industry. It enjoys one of New Zealand's sunniest climates, with warm, relatively dry summers and cool, crisp winters.

Tuamarina is a small town in Marlborough, New Zealand. State Highway 1 runs through the area. The Tuamarina River joins the Wairau River just south of the settlement. Picton is about 18 km to the north, and Blenheim is about 10 km to the south.