The Cueva de Don Justo (or Cave of Don Justo) is one of approximately 70 caves and
volcanic
A volcano is commonly defined as a vent or fissure in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.
On Earth, volcanoes are most often fo ...
galleries on the island of
El Hierro
El Hierro (), nicknamed ''Isla del Meridiano'' (the "Meridian Island"), is the farthest south and west of the Canary Islands (an autonomous community of Spain), in the Atlantic Ocean off the coast of Africa, with a population of 11,659 (2023). ...
in the Canaries.
The Cueva de Don Justo is over in length,
[ the cave is located in the El Lajial ]pahoehoe
Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or unde ...
lava field near the Orchilla lighthouse in the south of El Hierro, it is a wild cave that extends around the Irama mountain (also called Prim mountain) for a total distance of (with the parallel passages making up the extra distance).[
It was first explored and mapped by a speleological expedition in 1961, with further expeditions in 1974, 1976, and 1978, before the 1979 expedition completed the mapping of the of cave system.][ It is the longest of 28 known lava tubes on El Hierro,]lava tube
A lava tube, more rarely called a pyroduct, is a 'roofed conduit through which molten lava travels away from its vent'. If lava in the tube drains out, it will leave an empty cave. Lava tubes are common in low-viscosity volcanic systems. La ...
in the Canary Islands
The Canary Islands (; ) or Canaries are an archipelago in the Atlantic Ocean and the southernmost Autonomous communities of Spain, Autonomous Community of Spain. They are located in the northwest of Africa, with the closest point to the cont ...
, and the 13th longest in the world.[
The cave has a maximum depth of 135 to and at some points has up to 8 passages running in parallel.][ The cave contains well developed troglobitic fauna including seven species of ]troglobitic
A troglobite (or, formally, troglobiont) is an animal species, or population of a species, strictly bound to underground habitats, such as caves. These are separate from species that mainly live in above-ground habitats but are also able to live u ...
fauna exclusively found in this cave.[ The Cave is gated to protect these species,]
References
El Hierro
Don Justo
Don Justo
Volcanism of the Canary Islands
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