Dahab, South Sinai tide times

Dahab was a Bedouin fishing camp before it became a destination. That sequence still shows in the layout: the town runs along a single coastal road, the lagoon beach is the social centre, and the dive sites are accessed by walking north along the coast track or loading gear onto a small truck. The Sinai mountains rise immediately inland — bare red granite ridges that catch the light from sunrise through to late afternoon before the shadow line crosses the valley floor. The combination of mountain backdrop and clear Gulf of Aqaba water defines the visual character of Dahab as much as any specific feature.

The Gulf of Aqaba is a narrow, deep rift running north from the Red Sea proper. At Dahab, the tidal regime is semidiurnal: two broadly equal highs and two broadly equal lows each day. The mean range at Dahab is 0.8–1.2 m, larger than the central Red Sea minimum but still moderate by global standards. The Gulf acts as a tidal funnel: the further north you travel toward the closed end at Eilat and Aqaba, the larger the range becomes, reaching 1.5–2.0 m at the head of the Gulf. At Dahab, midway up the Gulf, the range is in the transitional zone — noticeable but not dramatic.

The Lagoon — the main beach area fronting Dahab town — is sheltered by the reef crest offshore. The reef creates a shallow, protected flat of 0.5–1.5 m depth at low water, deepening to 2–3 m at high. Shore entry to the house reef is from the reef edge, where the flat drops to the reef slope. At low water the edge is more easily located and the short swim across the flat is shallower; at high water there is more clearance over the coral but the edge position is slightly harder to judge for first-time visitors. Both tidal states are diveable; the difference is in entry logistics rather than dive quality.

The Blue Hole is 8 km north of Dahab town on the coastal track — a roughly 20-minute drive or 2-hour walk along the shore. It is a roughly circular submarine sinkhole, approximately 300 m in diameter at the surface, dropping vertically to around 100 m depth. The rim of the sinkhole is at the surface, meaning you enter directly into open blue water from shore. The site's notoriety comes partly from the Arch: a passage connecting the interior of the Blue Hole to the open sea, starting at around 52 m on the Blue Hole side and exiting at about 56 m on the outer reef wall. The Arch itself is approximately 26 m long. Reaching and transiting the Arch requires technical dive planning — it sits well beyond recreational dive limits. The Blue Hole is diveable and frequently dived at recreational depths on its interior walls down to 30–40 m; the wall has healthy soft coral and fish life at those depths. The site's fatal history is associated specifically with attempts to reach or transit the Arch without adequate trimix planning and training.

Freedivers use the Blue Hole differently. The open circular water column in the interior is used for constant-weight and free-immersion training; the geometry — calm, enclosed, and deep — makes it one of the more famous freediving training locations in the world. World records have not been set here, but the site has hosted national and unofficial record attempts. The freediving community in Dahab has operated continuously since the late 1990s and is a significant part of the town's identity.

The Canyon, south of Dahab town, is a different geological feature: a narrow crack in the reef flat that widens into a passage descending to around 52 m. The entry is from the reef flat, and the passage requires navigating a narrow chimney section before opening into the canyon proper. It is a recreational dive site (to 30 m) and a popular introduction to overhead environment diving. Canyon access is at any tide; the shallow reef flat crossing to the entry point is easiest at mid-to-high water.

For beach families, The Lagoon is a practical beach with calm, clear water and visual depth gauging possible from the surface. The reef edge is clearly marked with buoys in the main swimming area. The tidal range of 0.8–1.2 m changes the character of the inner flat across the cycle: at low water the flat is very shallow and warm, favoured for small children; at high water there is more depth and clearer separation between swimmer and diver zones.

Photographers working Dahab typically shoot the Blue Hole at dawn before the wind arrives — the surface of the sinkhole reflects the sky cleanly in the first hour after sunrise. The Sinai mountain light in the late afternoon throws warm colour onto the granite faces visible from the Lagoon beach. The town itself photographs best before 09:00, when foot traffic is low and the light is lateral.

Tide data for Dahab, South Sinai comes from the Open-Meteo Marine API, a gridded model product. Timing accuracy is ±45 minutes, height accuracy ±0.3 m — usable for trip planning, not for navigation.