The residential part of the suburb is located to the east and south-east of Maungakiekie / One Tree Hill, from which it takes its name, with the volcanic peak located within the suburb's boundaries.

Cornwall Park and Maungakiekie are major attractions within the suburb.

The results were 58.7% European (Pākehā); 9.4% Māori; 12.5% Pasifika; 27.1% Asian; 4.1% Middle Eastern, Latin American and African New Zealanders (MELAA); and 2.0% other, which includes people giving their ethnicity as "New Zealander".

[5] Of those at least 15 years old, 1,647 (44.4%) people had a bachelor's or higher degree, 1,350 (36.4%) had a post-high school certificate or diploma, and 705 (19.0%) people exclusively held high school qualifications.

[9][10] One Tree Hill existed as a separate borough from 1930 until 1989, when it was absorbed into Auckland City.