Caves are dark and hollow. They can form underground, on hillsides, or in the walls of cliffs. Some caves were carved out by water. Others were formed by lava that cooled and hardened.
StalactitesstalactitesALUMA IMAGES/GETTY IMAGES
a pointed piece of rock that hangs from the roof of a cave
(noun)Be careful not to hit your head on a stalactite. and stalagmitesstalagmiteALI MAJDFAR—GETTY IMAGES
a pointed piece of rock that sticks up from the floor of a cave
(noun)Inside the cave, be careful not to trip on a stalagmite. are sometimes found in caves. They are built up from the minerals in dripping water.
A person who explores and studies caves is called a spelunkerspelunkerCOREY HOCHACHKA—DISIGN IMAGES/GETTY IMAGES
a person who explores caves
(noun)Morgan is a spelunker. . There is a lot to discover in this unique habitat!