The heart-shaped opening is formed by the intersection of the sinkhole's circular rim and the walking path's perspective.
The cave walls exhibit alternating layers of red and black scoria, indicating the history of volcanic eruptions in the region.
The sinkhole is technically classified as a collapse doline, where the roof of a sea cave fell into the ocean-carved void below.
The cave is connected to the adjacent Touji Sand Skiing Area, which features a natural sand dune formed by wind carrying sand from the beach.
Ryugu Sea Cave is a natural sea cave featuring a large skylight opening created by the collapse of its ceiling. The cave is situated along the Izu Peninsula coastline in Shizuoka, Japan. Its distinct heart-shaped profile is visible when viewed from the observation path located above the opening. The geological structure is composed of scoria layers deposited by past volcanic activity, which have been eroded by wave action over time. Visitors can access the interior of the cave via a short walking trail. The site is a registered geosite within the Izu Peninsula UNESCO Global Geopark. The interaction between tidal changes and the cave entrance creates varying water levels within the rock formation.
The observation deck on the cliff top provides the best vantage point for capturing the heart-shaped opening.
Walk the circular path around the cliff edge before descending into the cave to see the heart shape from above.
Wear closed-toe footwear with good grip as the interior path can be damp and uneven due to sea spray.
Visit during low tide to see more of the cave floor and avoid water splashing into the interior walkway.
Do not attempt to climb the steep or unstable walls of the rock formation, as they are composed of loose volcanic debris.
