Mount Takamagahara (高天原山, Takamagahara-yama) is a mountain in the Gunma Prefecture of Japan, near Ueno village. Its measurement is 1,978.6 metres (6,491 ft 6 in) tall.
The crash of Japan Airlines Flight 123 on August 12, 1985 was initially reported on Mount Osutaka, but later confirmed to be on the ridge of Mount Takamagahara at a height of approximately 1,565 metres (5,135 ft) above sea level. Claiming the lives of 520 people, it is the deadliest single-aircraft plane accident in world history.
This area was later renamed as Osutaka no One ("Mountain Ridge of Mount Osutaka") by the village mayor of Ueno, Takeo Kurosawa. There is a shrine on the summit of the ridge to commemorate the lives lost in the crash of JAL123. The mountain road to the shrine was constructed as part of a compensation package from JAL.
35°59′30″N 138°41′20″E / 35.991779°N 138.68875°ECoordinates: 35°59′30″N 138°41′20″E / 35.991779°N 138.68875°E