But how are caves formed? Archaeological finds show that these were made from two things. The first is water while the second is from the remains of plants and animals that release carbon dioxide into the atmosphere.

When carbon dioxide mixes with hydrogen, it starts a chemical reaction to form carbonic acid. This is able to dissolve limestone producing stalactites or stalagmites that leave make up the rock formation in the cave.

There are different types of caves and the number really depends on the geographic location.

? Along the coastline, people will be able to see Sea Caves that were formed as waves crashed upon the rocks.

? Should you live somewhere up north, there is a chance there are glacier caves that were formed when the ice melts.

? Solutional caves are the ones caused by a chemical reaction.

? Talius caves are formed when rocks fall from the cliffs and create a big hole in the ground. Explorers will have to use a rope since there is only one way in or out.

These natural wonders as some call it may stretch for miles deep into the earth. Scientists have a lot to learn since this is only being studied in the last 2 centuries when the world has been existence for more than a million years.

The field of study is called speleology and those who are engaged in the research are called spelunkers. The research these people acquire will be able to tell geologists and other specialists the history of this place as well as its environment.

Lately, people don't only visit caves for research purposes. Some people have turned this into an extreme sport where players go in to find some treasure or enter one end and come out the other side.

When entering the cave, the person must have protective equipment. This involves wearing helmet, carrying a flashlight, having shoulder and kneepads, gloves and a lot of rope.

It is best to go in with someone who has been there before to serve as a guide because it is possible to get lost and trapped inside. Some of the most knowledgeable people are farmers, fishermen, hunters and miners who live near one or have spent some time exploring beneath the rocks.