Bluff, previously known as Campbelltown and often referred to as "The Bluff", is a town and seaport in the Southland region, on the southern coast of the South Island of New Zealand. It is the southernmost town in mainland New Zealand and, despite Slope Point and Stewart Island being further south, Bluff is colloquially used to refer to the southern extremity of the country. According to the 2018 census, the resident population was 1,797, a decrease of 6 since 2013.

Southland is New Zealand's southernmost region. It consists mainly of the southwestern portion of the South Island and Stewart Island/Rakiura. It includes Southland District, Gore District and the city of Invercargill. Murihiku Southland is bordered by the culturally similar Otago to the north and east, and the West Coast in the extreme northwest. The region covers over 3.1 million hectares and spans 3,613 km of coast. As of June 2023, Southland has a population of 103,900, making it the eleventh-most-populous New Zealand region, and the second-most sparsely populated.