Cromwell is a town in Central Otago region of the South Island of New Zealand. Cromwell is located on the shores of Lake Dunstan where the Kawarau river joins Lake Dunstan. Cromwell was established during the Otago gold rush and is now more known as one of the sub regions of the Central Otago wine region. In 2018, the town of Cromwell was home to a population of 5610 people.

The Kawarau River is a river in the South Island of New Zealand. It drains Lake Wakatipu in northwestern Otago via the lake's Frankton Arm. The river flows generally eastwards for about 60 kilometres (37 mi) and passes through the steep Kawarau Gorge until it joins Lake Dunstan near Cromwell. Before the construction of the Clyde High Dam, the Kawarau joined the Clutha River / Mata-Au in a spectacular confluence at Cromwell. The Shotover River enters the Kawarau from the north; the Nevis River enters it from the south. With many rapids and strong currents, the river can be dangerous and has claimed many lives. It is popular for bungy jumping and kayaking.