The Samaesan Hole is a technical diving site is located in the Gulf of Thailand, Samae San Island, in Sattahip District, Chonburi Province. The local vicinity is renowned for its technical diving and has numerous entries on the List of deepest dive sites in the Gulf of Thailand, with the deepest being the Samaesan Hole, with a recorded depth of 85m to 100m. The dive site lies in the vicinity of the shipping lanes between Koh Rong Nang and Koh Samaesan by the area named Explosives Dumping Ground on local sea charts.
The first successful recorded descent to the bottom of the Samaesan Hole occurred in 1998 by technical divers Steve Burton and Claes Martinsson.
The Samaesan Hole has gained popularity due to the number of hazards associated with this dive site. Specific documented risks include the following...
Due to the high number of risks, media tends to report this as dangerous location and dive site. More specifically it is recognised by Red Bull as one of the most extreme dive sites in the world, whilst Under Current Dive Magazine recognised it as a "deadly" dive site, alongside the Blue Hole (Red Sea). Renowned technical diver Mark Ellyatt referred to it as the "Black Hole of Death" by virtue of its "dark and horrible" nature combined with a number of recent victims the hole had taken when he dived there.