Taiwan's largest area of geological collapse, it was formed by intense headward erosion produced by the Chenyoulan River. At the headwaters, it was formed as the result of massive landslides.
這個台灣最大的崩塌地，形成原因是陳有蘭溪急速的「向源侵蝕」，在源頭處形成激烈的山崩土瀉而造成。