Nosy Be · Madagascar · Wall · Cave & cavern
Greg's Wall
A tunnel and arches cut through a gorgonian wall below 30 m
Area photo: Diego Delso · CC BY-SA 4.0
Greg's Wall is a deep wall in the Radama Archipelago, a little south of Antanimoro, plunging from a reef plateau into the depths and carpeted with immense gorgonians. Tunnels, arches and a few caves cut into the rock at depth, and the remote channel setting brings the chance of a whale shark or manta passing in the blue.
Also known as Greg Wall.
Where it is and how deep
14.1139° S, 47.6614° EApproximate position — the dashed circle shows where the site lies; your operator's briefing has the mooring.
The dive
The dive starts on the reef plateau at 13 m and drops over its edge onto the wall. Below 30 m the face is festooned with giant gorgonians, and opposite the wall a rock column runs down to the bottom. Between 32 and 38 m the route passes through a tunnel and a set of arches.
A few caves open into the wall at depth, so divers carry a torch to look inside. Eyes turned away from the reef toward open water may pick out a whale shark or a manta passing by.
Marine life and season
- Whale sharks
- Manta rays
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Off-season | Off-season | Fair | Good | Good | Good | Good | Good | Good | Prime | Prime | Good |
Season follows Nosy Be: Cyclone season (Jan-Mar) shuts down most diving; whale sharks aggregate Oct-Dec and humpback whales pass offshore during the austral winter.
Know before you go
- Strong current can run through the channel past the wall.
- The wall keeps dropping to about 70 m below the tunnel and arches, so depth needs close watching.
Dive videos
Greg Wall, le tunnel. croisière plongée Radama, Nosy Be Madagascar · Sakalav Diving on YouTube
greg's wall. ILES RADAMA · MENABE PLONGEE on YouTube
Questions divers ask
What certification does Greg's Wall need?+
It is an advanced dive: the tunnel and arches lie between 32 and 38 m, and strong current can run through the channel.
Sources
- Greg's Wall, Radama Archipelago — DivePlanner Pro
- Madagascar diving destination — DUNE
- Croisière plongée Madagascar — vvanat
- Advanced diving Madagascar — Original Diving
- Séjour aux Radama — Scuba Nosy Be
More dive sites in Nosy Be
Reef
Coral plateau with fusilier shoals, turtles and passing grey sharks
Seamount
A 500 m dome where grey reef and leopard sharks patrol the slopes
Wall
Sheer walls where barracuda, mobulas and whitetips pass
Wall
A deep drop-off off Nosy Iranja with a fair chance of big fish
Reef
A long soft-coral reef thick with reef fish, kept for the third dive
Pinnacle
Two rock peaks breaking the surface, cut through with arches and caves
Artificial reef
A scuttled trawler at 28.5 m off Nosy Sakatia
Reef
Leopard, grey and whitetip sharks on a hand-shaped reef
Similar dives elsewhere
Wide soft-coral overhangs under table corals along a 4 km back reef
The best-known whale shark spot on South Ari's outer reef
An open-top cave in the northwest wall of a limestone island
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An undercut in the wall at 40 m, west of Ski Run