Ponta do Ouro · Mozambique · Reef
Riana's Arch
A small swim-through with hawkfish and pipefish on the rock
Area photo: Derek Keats · CC BY 2.0
Riana's Arch is a mid-depth reef built around a small swim-through, dived between 19 and 25 m. The arch is the feature divers come for, and the rock around it carries a heavy load of macro life: long-nose hawkfish, scribbled and red-banded pipefish, two-bar anemonefish and nudibranchs, with a wide variety of fish through the swim-through itself.
Also known as Rianna's Ledge.
Where it is and how deep
No published position for this site — the map shows Ponta do Ouro and its other sites; operators know the mooring.
The dive
Underwater Explorer dives this one between 19 and 25 m, so it sits in the mid-depth range and comes with a bounded bottom time. The swim-through is the organising feature of the dive: the boat puts you in near it, you work the rock on the way to the arch, pass through, and then spend what gas is left on the reef around it rather than pushing on for distance.
The arch is small, and the variety of fish moving through it is the reason it is dived rather than any length of passage. Around it the reef is worth going slowly over: long-nose hawkfish perched on the rock, scribbled and red-banded pipefish, fierce two-bar anemonefish in their anemones and nudibranchs on the harder ground. It rewards a camera and a light more than it rewards covering ground.
Marine life and season
- Nudibranchs
- Macro critters
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Good | Good | Good | Good | Good | Good | Prime | Prime | Prime | Prime | Good | Good |
Season follows Ponta do Ouro: Resident dolphins are seen year-round; shark activity at Pinnacles and whale migration peak July-October.
Know before you go
- The swim-through is an overhead, however short: go through one at a time with fins under control and do not enter it silted or crowded.
Questions divers ask
How deep is Riana's Arch?+
The site is dived between 19 and 25 m. The swim-through sits within that band, which puts it beyond entry-level depth limits and inside the range that needs a planned bottom time.
Sources
- Riana's Arch — Scubago
- Reef Diving — Underwater Explorer
More dive sites in Ponta do Ouro
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A 21 to 24 m ledge with nudibranchs and passing game fish
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Game fish over a reef averaging 25 m
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Hammerheads and Zambezi sharks off a reef edge in open water
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Overhangs and arches on a shallow fossil-dune reef
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Frogfish, morays and rays on a 20 m reef
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Octopus, potato bass and moray eels on a shallow reef
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Bass, basslets and garden eels on a 20 m reef
Similar dives elsewhere
Air-trap overhangs and swim-throughs on a granite boulder reef
Three sponge-covered pinnacles off the Rooi-els shore
Noble coral on every pinnacle, above sheer walls to the sand
A flower-like anemone full of shrimps and pipefish