Mini Grotto on Shimoji Island is a cave site accessible by boat. The topography features an overhead environment with depths ranging from the surface down to 20 metres. Conditions are generally mild, though divers and snorkellers must maintain awareness of the overhead structure and control their buoyancy while navigating the cave. The site is suitable for beginners, provided they remain within their comfort levels regarding the cavern depth. Water temperatures fluctuate between 23 and 30 degrees Celsius throughout the year. Hazards include the overhead environment and the presence of lionfish; maintain a safe distance from these fish to avoid stings while exploring the shaded ledges.

Tori Ike is a complex site on Shimoji Island featuring a blue hole, cave system, and deep drop-off. Divers experience depths between 23 and 45 metres, with an average of 35 metres. The site is characterised by thermocline and halocline phenomena where freshwater and saltwater layers mix. Visibility typically ranges from 20 to 40 metres. Due to the overhead environment, significant depth, and strong, shifting currents, this site is reserved for advanced divers. Access is by boat only, with a typical dive duration of 30 minutes. Divers must maintain strict buoyancy control and monitor air consumption throughout the cave sections.

Antonio Gaudi is a boat-access reef and cave site located off Shimoji Island. The topography features complex cave structures that require careful air management and buoyancy control. Divers typically explore depths ranging from 18 to 35 metres, with an average depth of 28 metres. Conditions include moderate to strong currents and visibility reaching up to 30 metres. Due to the depth and current, this site is suited for intermediate divers. Access is strictly by boat, and divers should monitor their depth gauges closely while navigating the cave sections. Always follow local guide briefings regarding current shifts and timing for cave entry.

Nakanoshima Channel on Shimoji Island offers a diverse marine environment featuring reef, cave, and drift diving. Divers can explore depths ranging from 5 to 20 metres, with an average depth of 15 metres. The site is accessible only by boat, and the mild currents make it suitable for beginners. Visibility typically ranges between 10 and 30 metres. Water temperatures are warm, fluctuating between 23 and 30 degrees Celsius throughout the year. Divers should exercise caution regarding surge and swell conditions, and avoid contact with sharp coral and rocks while navigating the reef and cave sections.

Nakanoshima Hole is a cave and reef system located off Shimoji Island. The site features depths ranging from 5 to 26 metres, requiring boat access. Divers and snorkellers should be prepared for strong currents that can shift direction within the cave structure. Due to the overhead environment and current conditions, this site is suited for intermediate divers with strong buoyancy control skills. Water temperatures fluctuate between 23 and 30 degrees Celsius throughout the year. Visibility is variable, and it is recommended to consult with boat operators regarding current conditions before descent. Always remain close to your guide when navigating the cave sections.

Marine Lake on Shimoji Island offers a unique combination of cave and reef diving within a sheltered, land-locked marine environment. Divers can explore depths ranging from 5 to 17 metres, where mild currents generally prevail. The site is accessible via shore entry and is suitable for newly certified divers. Visibility at this location is variable, so checking local conditions before a dive is recommended. Night diving is permitted, providing an opportunity to observe the site under different conditions. Due to the presence of jellyfish, wearing full body protection such as a full wetsuit or skin suit is essential for all divers.

The Devil’s Palace is a cave system located off Shimoji Island, Japan, featuring depths ranging from 5 to 28 metres with an average of 15 metres. This site is strictly for advanced divers due to the overhead environment, which lacks direct vertical access to the surface. Divers must maintain neutral buoyancy and monitor air supply carefully while navigating the caves and swim-throughs. Visibility is high, typically between 30 and 40 metres. Access is by boat only, and conditions include mild currents. Divers should carry both primary and backup torches, as the cave interior significantly reduces ambient light. Facilities for boat access vary seasonally.

Naruhodo The Cave is a boat-access dive located off Shimoji Island. The site features an overhead environment with depths ranging from 15 to 18 metres. Divers should be prepared for variable visibility and must maintain careful buoyancy control to avoid contact with the cave structure. Currents at the site are generally mild, though the overhead nature of the cave requires constant awareness of surroundings and exit paths. Due to the limited natural light in deeper sections, carrying both a primary and backup torch is essential. This site is suitable for beginners, though comfort in confined spaces is necessary for navigating the cave environment safely.