Rapa Nui has one of the world\u2019s highest density of lava tubes. Apart some sporadic visits in the 1960s and 70s speleologists have become interested in this island only recently (see speleological references below).
The present paper presents the exploration and the research carried out in the framework of three international speleological expeditions to Rapa Nui (2005, 2007, 2008) organized by the Sociedad de Ciencias Espeleologica Alfonso Antxia from Bilbao (Spain)
