Police in Berks County said they were called to Dyers Quarry in Union Township shortly before 6 p.m. Saturday.
Although police were initially told that the victim had fallen 50 feet, they found that 27-year-old Elizabeth McKibbin of Elverson fell more than 300 feet.
Investigators said she had been at the quarry with five other adults and two young children.
They said interviews indicated that she had been "dancing on the rock ledge" when she slipped and fell down the cliff into the quarry, which is filled with water.
Emergency responders recovered her body and she was pronounced dead at the scene.
------
Send a News Tip to Action News
Learn More About 6abc Apps