Caves are one of the most interesting natural formations known to humans. For the longest time, people have been using caves as shelter, and whole civilizations have thrived due to their protective characteristics.
The most general definition of a cave is a part of the Earth’s core that has emptiness or open space which is connected with the surface in one or more places. It can either be lighted by the sun through an opening directly above the open space or it can be lighted at an angle from a side opening. Some caves consist of several passageways and labyrinths while others have one or two big open “halls”. Some of the known caves stretch for tens or even hundreds of kilometers, and others are extremely small. Some caves are at the ground level, directly under the surface of the earth, others are found in mountains and some can only be accessed by water.
There are many types of caves, as well as the processes of their formation. Corrosion caves are formed by the erosion of water which carries large boulders. Water is a great force that erodes the rock, taking hundreds or even thousands of years to make. Another formation process relates to glaciers that move through an area, or an ice formation inside a mountain massive which melts, leaving behind a large space. Fracture caves are characterized by the collapse of softer layers inside a more hardened formation. Unfortunately, only a small portion of the world’s caves have been studied by cavers in detail. Europe is one of the places where there are a lot of caves known to people while other parts of the world are mostly unexplored. Overall, caves present great historical, cultural, and geological interest to scientists and archeologists, so a close study of all the caves in the world is required.