Karetai Peak is part of the Darran Mountains and it is situated nine kilometres east of Milford Sound in the Southland Region of the South Island.

It is set within Fiordland National Park which is part of the Te Wahipounamu UNESCO World Heritage Site.

Topographic relief is significant as the summit rises 1,300 metres (4,265 feet) above the Donne Valley in one kilometre.

[6] Prevailing westerly winds blow moist air from the Tasman Sea onto the mountains, where the air is forced upward by the mountains (orographic lift), causing moisture to drop in the form of rain or snow.

The months of December through February offer the most favourable weather for viewing or climbing this peak.