The area is dominated by the vast Hardangervidda plateau in the east and the large Folgefonna glacier on the central Folgefonna peninsula. The district was selected as the millennium site for Hordaland county.
The Old Norse form of the name was Harðangr. The first element could be harðr meaning "hard" (referring to wind and weather), or it could be referring to the Charudes, a Germanic tribe from Hardsyssel, Denmark. The last element is angr "tight fjord" (the name originally belonged to the fjord, now called Hardangerfjord).