St John's Reefs · Egypt · Cave & cavern · Reef
Umm Kharārīm
Sunlight falling through cracks in the cavern roof at 6-10 m
Area photo: Derek Keats · CC BY 2.0
Umm Kharārīm is the cave dive of St John's: a network of interconnected caverns and tunnels eroded into one large reef block over millennia, sitting in only 6 to 10 metres of water alongside a coral garden. Divers come for the light rather than the fish, following guide-led swim-throughs between chambers where sunlight breaks through cracks in the roof.
Also known as Umm Chararim, Umm El Khararim, St John's Caves.
Where it is and how deep
23.4147° N, 35.9386° EApproximate position — the dashed circle shows where the site lies; your operator's briefing has the mooring.
The dive
There is no descent to speak of. The whole site sits in the shallows, so you drop onto a coral garden in 6 to 10 metres and stay there for the dive. The reef block above and around you is riddled with connected tunnels of different lengths and widths, eroded into the coral over millennia, and you thread them one at a time. It is an open structure rather than true cave — a series of caverns and swim-throughs where you are never far from an exit or from natural light.
The reason to dive it is the illumination. Sunlight streams down through cracks in the ceiling of the chambers, and photographers work those shafts against the coral topography rather than waiting on marine life; the site is popular precisely because it delivers without depending on what swims past. What it does demand is excellent buoyancy control. Sources that call the dive safe say so in the same breath as that warning: this is coral on every side, and a careless fin stroke costs you both the visibility and the reef, so trim matters more here than any number on the computer.
Marine life and season
The sources we used don't single out particular species here.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Fair | Fair | Good | Prime | Prime | Prime | Good | Good | Prime | Prime | Good | Fair |
Season follows St John's Reefs: Mar–Jun and Sep–Nov are the settled windows; midsummer is very hot and winter northerlies make the long crossing uncomfortable.
Know before you go
- The caverns are open swim-throughs rather than true cave, but coral is within fin reach for most of the dive — hold your trim and stay off the walls and ceiling.
Dive videos
2024-05 Umm Chararim cave reef in Egypt swim through 4K HDR · AquaVista Journeys (with RomiK) on YouTube
Questions divers ask
How deep is Umm Kharārīm?+
Shallow. The caverns and the coral garden run at 6 to 10 metres, so the dive is limited by buoyancy and light rather than by depth or no-decompression time.
How do you get to Umm Kharārīm?+
By liveaboard only. The site is deep in the southern Egyptian Red Sea and needs an extended cruise from the Marsa Alam hub at Port Ghalib; there is no day-boat access.
Sources
- Umm El Khararim (St. John's Caves) Marsa Alam: Light-Filled Caverns & Soft Coral Labyrinth — Sambo Divers
- 22 Saint John's reef dive sites + MAP & reviews — scubadiving.place
- St. John's - Best Red Sea Liveaboard Diving In Southern Egypt — No Troubles Just Bubbles
- Umm Hararim Cave Reef — dive site details — scubadiving.place
In The Logbook
- Cavern and cenote diving without cave trainingCaves & caverns · 8 min read
More dive sites in St John's Reefs
A maze of coral columns down to sand at 20 m
Short caverns at 7 m under an overnight mooring
Tunnels and fissures cut into an 840 m reef block
Wall
Overhangs on the southern wall and a cavern you enter at 10 m
Grey reefs and hammerheads off an exposed pinnacle
Pinnacle
A ledge at 20–35 m circling a current-swept habili
Similar dives elsewhere
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A reef fissure opening at 18 m onto a chamber floor at 30 m
Cave & cavern
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A cave roof with amphorae fixed into the rock
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