Thomas reef

Soft coral starts almost immediately. Entering from the south side along the eastern wall, the reef drops away in curtains of Dendronephthya and large gorgonian sea fans. Look closely at the fan branches for longnose hawkfish, barely 10cm long and almost invisible against the lattice. The east wall descends to a sandy plateau at 25-30m, where the reef's inner curve shelters a quieter zone before the canyon entrance.

Rounding the north end, the wall becomes more broken. Splits and shelters in the rock harbour dense schools of glassfish. Then the west wall takes over, darker and more dramatic, with overhangs and small caverns packed with sweepers. Barracuda cruise here in loose formations. In summer, the largest tuna appear along this face. The smallest Tiran reef is also the most feasible to circle on a single tank, and the changing character of each wall section means the dive never flattens out.

Thomas Reef holds two reputations that rarely share the same site. Above 30m, it is the most colourful wall dive on the Tiran circuit. Below 35m, it becomes something else entirely. A sandy plateau on the south side opens into a crack in the reef, the entrance to a canyon that descends through overhead archways and narrow passages to about 90m. One experienced diver put it simply after comparing Thomas Canyon to the more famous Canyon at Dahab: "much nicer, and empty." Operators restrict canyon access to divers with documented deep permissions, which keeps traffic low and the environment intact.

The reef's lack of mooring points adds to the experience. Boats cannot anchor, so drift diving is the only option. Currents can be fierce, particularly at the northern tip where down currents develop, driven by the strong flow forced through the bottleneck of the Straits of Tiran1. This is not a site that forgives inattention. It rewards it with coral density that divers consistently rank first among the four Tiran reefs.

Thomas Reef sits in an exposed position in the Straits of Tiran. North winds can cancel the trip entirely, and conditions change quickly. Carry an SMB and deploy it during your safety stop. Boats will be circling, not moored. Currents are strong and unpredictable, including down currents at the northern tip. Stay close to the wall for shelter if the current picks up.

The canyon is not a recreational dive. Entry at 35m requires Deep Diver specialty at minimum, and the full descent to about 90m demands technical certification with trimix. Divers have become stuck in the overhead environment inside the canyon. Do not enter without appropriate training and equipment.

Morning dives offer the best natural light for photography on the east wall's soft corals and gorgonians. Thomas Reef is a standard stop on Tiran day trips from Sharm El Sheikh, usually combined with Jackson and Gordon reefs. The boat ride from Na'ama Bay or Sharm el Mina takes 1.5 to 2 hours. The Tiran reefs sit within Ras Mohammed National Park, Egypt's first national park, so there are no moorings and nothing may be taken from the reef2.