What are caves?

Most rocks have pores and cavities within them. Generally, however, these are not large enough for a person to explore. Caves are cavities or hollow spaces inside a rocky mass that are large enough for a person to explore. There are many types of caves formed through different processes : some are small, and it is difficult for man to penetrate into; others, on the contrary, stretch underground for tens or hundreds of kilometres, reaching depths of over 2,000 m. Formation processes control lenght, development and shape of a cave, and also the difficulties that will arise when exploring them. Most of the longest and deepest caves do not consist in an isolated cavity, but they form a system, which at times may be very complex, made of rooms, sinkholes, shafts, meanders, canyons, interconnecting galleries, which are arranged to form a system or karst complex.
Large quantities of underground water move through karst systems, caves may therefore be classified in different sub-areas, i.e. occupied by air and completely dry or scoured by streams, they may be flooded at times, or permanently invaded by fresh and salt water.

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Facts

  • 24 February 2011

    And in underground tunnels?

    There are groups of terrestrial animals that eat insects, worms and other invertebrates...

    13 May 2011

    The climate underground

    Going down deep in the Earth’s crust, the temperatures increase gradually...

  • A walk underground

    The longest caves in the world are in Kentucky, the caves of Mammoth...

    Ice in caves

    In high mountain or high latitude environments, many caves can contain ice deposits...

  • Amphibians in a cave

    Proteus is an amphibian of white-yellowish or light pink colour...

    Can you breathe in a cave?

    One of the most common beliefs is that in caves the air is often stuffy...

  • 24 February 2011

    And in underground tunnels?

    There are groups of terrestrial animals that eat insects, worms and other invertebrates...

  • 13 May 2011

    The climate underground

    Going down deep in the Earth’s crust, the temperatures increase gradually...

  • A walk underground

    The longest caves in the world are in Kentucky, the caves of Mammoth...