The Devil's Teeth Rocks are within the caves of the Gaddon where a mighty subterranean river flows. At one point the river runs over a waterfall down into the Devil's Teeth Rocks, so named because most who encounter them on the river meet their doom here. They are tall, hard rocks, made sharp and jagged by the action of the water around them and have formed at the bottom of the falls where there is almost no chance of escape.