* Dissolving rock: Water, especially slightly acidic rainwater, can dissolve certain types of rock, like limestone, dolomite, and gypsum. This is called karst erosion.

* Chemical reactions: The carbonic acid in rainwater reacts with these rocks, breaking them down and creating caverns, tunnels, and other cave features.

* Mechanical erosion: Water also carries sediment and debris that can wear away rock through abrasion.

Other factors that contribute to cave formation:

* Geological processes: Tectonic movements can create fractures and faults, providing pathways for water to flow.

* Climate: Areas with high rainfall and specific types of rock are more prone to cave development.

* Time: Cave formation is a slow process that can take millions of years.

Let me know if you'd like to learn more about specific types of caves or cave features!