Ice caves form when the inside of the glacier melts and the hole gets bigger and bigger.  Then it forms a cave with solid ice and hard packed snow.  If you want the cave  entirely of ice you need a cold climate.  It is so cold that most people don't visit it without the proper equipment.  The formations in the ice cave are very easy to break.  All the formations in a ice cave  are made entirely of ice.  Sometimes soft step the floor below can break.  

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