This image illustrates the character of break down portions of some passages in Mammoth Cave. Breakdown is attributed to both the unloading of rock once stream retreat from sections of the cavern and falls associated with the shaking of major earthquakes in the past. Breakdown usually results in creating a arch- or dome-like passage which is a more stable ceiling arrangement. This break down is located in the Grand Central Station area of the Grand Avenue Tour of Mammoth Cave.
