Lungfengku used to be a strange lake called Tahuangshui, into whose water leaked great quantities of sulfur. Now Tahuangtzui refers to the basin mentioned before. Perhaps it's a case of passing down a mispronunced place name.
以前這裡曾經是一個湖，叫「大磺水」，為有硫氣噴出的奇異湖泊，諧音為「大磺嘴」，但現在大磺嘴則是指前面提到的盆谷，可能是地名誤傳。