A low-slung dayboat slips away from Marmaris harbor as the town's stone fortress recedes; salt and diesel mix on the breeze and the Mediterranean opens blue and roomy ahead. Instructors call a short pre-dive briefing on deck — regulator checks, hand signals, and a calm voice that keeps the sea from feeling intimidating. The first descent is deliberate: fins push through a thin glass of surface glare and the reef below takes on a slow-breathing life of its own. Schools of wrasse and damselfish orbit rock ledges while granite shelves and limestone outcrops create swim-throughs and shadowed pockets where octopus and groupers hide.