The track was known for having many fast corners, as well as noticeable changes in elevation during the course of a lap. Many considered the Österreichring to be dangerous, especially the "Boschkurve", a 180-degree right-hand corner with almost no run-off area. Tragically, American Mark Donohue died after crashing at the "Hella-Licht" corner in 1975. It is also known that four-times World Champion Alain Prost often said that all tracks can be changed but that the Österreichring should remain unchanged, just adding run-off areas would be fine.

Source: Wikipedia