red Fuji; Mount Fuji glowing red at sunrise
Refers to the natural phenomenon when Mount Fuji appears red, typically in the early morning from late summer to early autumn, due to the angle of the sun's rays.
In the early morning, the red Fuji was reflected on the lake surface.
I woke up before dawn to take a photo of the red Fuji.
Compound of 赤 (aka, 'red') and 富士 (Fuji, 'Mount Fuji'). The term describes the visual effect of the mountain appearing red under certain lighting conditions.