Dive log with a 30.8 m L-Arch entry and species notes including giant trevally, snappers, lionfish, and shrimps.
L Arch is a boat-access L-shaped arch off Irabu Island.
L Arch is a boat-access L-shaped arch off Irabu Island.
Local guide support is the standard way to dive the site.
L Arch is a boat-access L-shaped topography dive off Irabu Island with a long overhead arch, tunnel-like sections, and cave holes that make it a skill-first site. Current can be strong, so the dive rewards controlled buoyancy, calm pacing, and a comfortable attitude around overhead terrain. Expect schooling fish and smaller life around the walls and holes, with the structure itself doing most of the work.
Conservative baseline from public research. No community dives logged yet.
Depth range, seasonality, and planning context.
Reported Depth
15m - 35m
Depth Note
Local guides describe the arch and tunnel route as spanning roughly 15-35 m, with a deeper cave-like section under the arch.
Best Season
Summer, especially May to September, when Irabu is more favorable.
Typical Conditions
An advanced boat dive with long overhead sections, strong current on some dives, and clear water when the sea settles.
Site conditions, restrictions, and access requirements.
Site Conditions
Safety Notes
Watch current at the arch and cave entrance, keep buoyancy steady under overhead sections, and plan the dive with local guide support.
Access Restrictions
Boat access and local guide support are strongly recommended because of the overhead sections and current.
Legal Notes
Follow local guide and boat-briefing rules for overhead-environment diving.
Community notes to help plan your visit.
Scuba Diving
Boat-access topography dive with a long L-shaped arch, tunnel-like sections, and a cave; best for confident intermediate and advanced divers.
Freediving
Not a casual freedive site because the arch and tunnel are deep and overhead.
Snorkeling
Not a snorkeling site; the main features are deep and overhead.
Species commonly reported at this site, with direct links into their wildlife guides.
Community dive logs and visit reports for this site.
Average conditions based on logged dives & visits.
Planning answers for access, conditions, timing, and site logistics.
Last Updated
Research Sources
Dive log with a 30.8 m L-Arch entry and species notes including giant trevally, snappers, lionfish, and shrimps.
Dive-center page with a 20 m arch start, 35 m depth under the arch, and fish/crab observations.
Tourism feature placing L-Arch among advanced sites and favoring Irabu in summer.
Academic site note placing L-arch north of Irabu with a dark arch/cave profile and guide recommendation.
Operator guide with boat entry, 15-35 m depth, 20-40 m visibility, strong current, and summer seasonality.
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