Sunsets and sunrises in the mountains never get tired. Anyone who ever goes to the mountains knows what I'm talking about. 
Most people look towards the Sun at sunset (which is understandable), but if you look a little to the side, you'll see a dark band that gradually gets larger and is highest in the east. This phenomenon is certainly known mainly by mountain lovers, but few people know what this phenomenon represents.
 It is the shadow of the Earth. When the setting Sun casts its light on the Earth, the Earth's shadow is reflected in our atmosphere as a faint dark band. The next time you stay in the mountains or somewhere with a flat horizon, I definitely recommend observing. 

Photographed on February 11, 2025, Lomnický štít observatory, 2634m Slovakia
Canon 6D+Sigma 24mm