Small Reef/Three Tunnels

Small Reef, also known as Three Tunnels, is one of Fethiye's most architecturally dramatic dive sites, where natural rock formations have created a series of swim-through tunnels that give advanced divers the exhilarating experience of overhead environment diving within a natural reef setting. Descending to thirty meters along the Turquoise Coast, this site delivers the kind of adventure-diving that creates lasting memories and brings divers back to Fethiye again and again. The defining feature of this site is, as the alternative name suggests, its trio of tunnels that penetrate the reef structure at various depths and angles. These natural passages were carved by millennia of wave action and geological movement, creating swim-throughs that range from wide, light-filled corridors to narrower passages where the rock walls close in to create a genuine sense of entering the earth beneath the sea. The tunnels are large enough for single-file passage by divers, with sufficient clearance to avoid contact with the encrusted walls, though good buoyancy control is essential to navigate them safely and without damaging the delicate marine growth that lines their interiors. The experience of entering the tunnels is transformative. As divers pass from open water into the rock passages, the quality of light changes dramatically. Sunlight filtering through the tunnel openings creates shafts of blue-white illumination that cut through the darker interior, producing natural lighting effects that are breathtakingly beautiful. Where the tunnels curve or narrow, pockets of near-darkness give way to sudden bursts of light at exits, creating a rhythm of shadow and brilliance that makes the transit feel almost theatrical. The acoustic environment changes too, with the sounds of breathing and bubbles amplified by the rock walls into an intimate, immersive soundscape. Outside the tunnels, Small Reef itself is a compact but richly colonized structure that supports diverse marine life. The reef rises from a sandy bottom, its rocky surfaces encrusted with the full spectrum of Mediterranean sessile organisms. Sponges in multiple species and colors create a patchwork of living texture, while sea fans and soft corals occupy the current-swept faces where water flow is strongest. The crevices and overhangs that characterize the reef's exterior provide shelter for the species that make Small Reef a genuinely interesting dive beyond its tunnel attractions. Marine life within and around the tunnels reflects the habitat diversity these structures create. The shaded interiors host species that prefer low light, including large lobster that back into the deeper recesses and moray eels that find the tunnel walls ideal for establishing dens. Cardinalfish school in the tunnel openings, their translucent bodies catching whatever light penetrates. Outside, the reef supports the typical Fethiye assemblage of grouper, bream, wrasse, and damselfish, with the added interest of species drawn to the unusual habitat that the tunnel structures provide. The advanced rating of Small Reef reflects both the depth and the overhead environment aspects of the dive. While the tunnels are natural formations rather than true caves, they share some of the same considerations: divers must be comfortable in enclosed spaces, maintain excellent buoyancy control to avoid contact with walls and ceiling, and be aware of their air consumption and proximity to open water at all times. Proper briefing by experienced local guides covers the specific routes through each tunnel, including exit strategies and behavior in the event of reduced visibility from disturbed sediment. Visibility at Small Reef is typically very good, with the offshore position and current flow maintaining clear conditions throughout the diving season. The clarity of the water is particularly important here, as it ensures that the tunnel interiors receive sufficient natural light to be safely navigated without artificial illumination, though a dive torch is always recommended to reveal the full color spectrum of the encrusting life within the passages. Small Reef and its Three Tunnels represent the adventurous side of Fethiye diving, a site where the natural architecture of the Mediterranean seabed creates experiences that rival purpose-built underwater attractions anywhere in the world.