Oʻahu · United States · Reef
Horseshoe Reef
Double horseshoe reef, nothing below 12 m
Area photo: mattk1979 · CC BY-SA 2.0
A double horseshoe-shaped reef off the south coast, no deeper than about 12 m and one of the most dived sites in the islands. The shallow profile suits new divers, but the water above it is busy with boats, so it is run as a boat dive rather than swum out to from the beach.
Where it is and how deep
21.2870° N, 157.8642° WPublished position for this site.
The dive
The reef is laid out as a double horseshoe, which gives the dive its shape: two curved arms of coral to follow with sand between and around them, none of it deeper than about 12 m. That depth is why it works for divers of any level, and why it is one of the most dived sites in the Hawaiian islands rather than only a local favourite.
Green turtles and triggerfish are the constants, and octopus is a regular find for divers who search the coral rather than swim over it. The reef also attracts bigger visitors — tiger sharks, manta rays and stingrays are all reported here, along with moray eels in the structure. Boat traffic overhead is the one thing to stay aware of on the ascent.
Marine life and season
- Sea turtles
- Tiger sharks
- Manta rays
- Stingrays
- Octopus & cuttlefish
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Good | Good | Good | Good | Prime | Prime | Prime | Prime | Prime | Prime | Good | Good |
Season follows Oʻahu: South-shore boat diving runs all year; the North Shore reefs at Pupukea are only calm from about May to October and are dangerous in winter.
Know before you go
- Boat and watersports traffic runs heavy over this stretch of the south coast, so ascents need a slow, listening approach and a marker up before surfacing.
Sources
- Horseshoe Reef - Hawaii — Scubago — Scubago / SSI MyDiveGuide
- Discover the Best Dive Sites in Honolulu — Rainbow Scuba Hawaii
More dive sites in Oʻahu
Reef
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Wreck
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Reef
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Wall
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Wall
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Similar dives elsewhere
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