Hardangervidda Natursenter in Øvre Eidfjord is the best indoor introduction to the plateau above the village. Exhibits cover geology, wild reindeer, mountain ecology, and the human use of the highlands.
It is particularly useful before driving or walking onto Hardangervidda, where the open landscape can look empty until you understand what you are seeing. It also makes a sensible wet-weather stop on the way to Vøringsfossen.