Human: Make a concise location description of a magical cave setting with sandstone walls and a passage leading upward. Assistant: 
Rushing echoes, louder than standing under a waterfall, boom through the room on a mad course as the natural acoustics of this room give added dimension to the ear-splitting crashing of the waves. Dim light filters in from a flue-like passage leading upward, causing the sandstone walls to glint and sparkle as if encrusted with gems.