Indonesia
A narrow strait in North Sulawesi separating the mainland from Lembeh Island, internationally regarded as the birthplace and benchmark of muck diving.
Lembeh Strait separates Sulawesi's mainland from Lembeh Island, with the town of Bitung on the western shore. It is known worldwide for muck diving over dark volcanic sand in search of cryptic critters such as frogfish, mimic octopus, blue-ringed octopus and mandarin fish. The Banggai cardinalfish, native elsewhere, was introduced here via aquarium-trade releases and has since spread across the strait. Estimates of dive-site numbers vary from over 60 to around 95. Source: Wikipedia (Lembeh Strait).