Kameiwa cave

About

Kameiwa cave and the Nōmizo waterfall that flows through it are located near the city of Kimitsu, Chiba Prefecture, Japan. While referred to as a cave, the Kameiwa cave is a tunnel bored during the Edo period to provide water for local agriculture. The cave and the waterfall gained attention in 2015, when photographs taken in the early morning of equinoxes posted on Instagram showed a heart-shaped image of sunlight throught the cave above the waterfall.

Adapted from Wikipedia (CC BY-SA). Photography via Wikimedia Commons.