The Blue Cave's signature glow is created by sunlight reflecting off the white limestone floor through a narrow underwater opening.
The site sits on an uplifted coral reef formation that has been eroded by wave action over millennia.
Cape Maeda is one of the few locations in Okinawa where shore access to high-density coral snorkeling is managed via a dedicated staircase.
The surrounding waters are a protected habitat for diverse marine life, including schools of soldierfish and sea goldies near the grotto entrance.
During the Ryukyu Kingdom era, the cape served as a strategic vantage point for monitoring coastal movements.
Cape Maeda is a prominent coastal landmark in Onna, Okinawa, best known for the Blue Cave, a sea grotto illuminated by natural turquoise light. The site features a cliffside observation deck offering panoramic views of the East China Sea and the Kerama Islands. Below the cliffs, a steep stone staircase provides direct access to the water for snorkeling and scuba diving. The underwater terrain consists of complex limestone formations and diverse coral reefs. Strong currents are common, necessitating adherence to local safety signage and lifeguard warnings. The area is part of the Okinawa Kaigan Quasi-National Park. Facilities include public restrooms, shower stalls, and a parking lot located at the top of the cliff. It serves as one of the primary entry points for boat and shore-based marine excursions in the region.
The upper observation deck facing west for sunset views, or the interior of the Blue Cave for its unique light effects.
Bring non-slip water shoes to navigate the limestone rocks and concrete stairs safely.
Check the official marine safety flags at the entrance; red flags indicate that water access is prohibited due to dangerous conditions.
If planning to swim in the Blue Cave, consider visiting during the off-season or early weekday mornings to avoid heavy crowds from tour groups.
Attempting to swim to the Blue Cave during high surf or without a professional guide, as current patterns inside the grotto can be deceptive.
The park may close access to the water during typhoons or periods of extreme sea turbulence.
Swimmers must wear a life vest at all times when in the water; removing footwear is required inside the shower and changing room facilities.
