當前我們所處位置的前方，視野突然變得狹窄，形成了一種獨特的“門狀”結構，我們將其稱為“南天門”。南天門頂端的鐘乳石以彎曲的形態生長，這在地質學上被稱為“彎曲石”。關于彎曲石的形成，它與洞內的風向緊密相關。由于洞內空氣存在南北對流現象，且風向會隨著季節的更替而發生變化，這種變化導致了洞頂滴水位置的偏移。進而，水中的礦物質在滴落過程中發生不定向的沉積，最終形成了我們所見的彎曲石。

In front of our current location, the view suddenly becomes narrow, forming a unique "gate-like" structure that we call the "South Gate of Heaven." The stalactites at the top of the South Gate of Heaven grow in a curved shape, which is geologically known as "curved stone." Regarding the formation of curved stone, it is closely related to the wind direction within the cave. Due to the phenomenon of north-south air convection in the cave, the wind direction changes with the alternation of seasons. This change causes a shift in the dripping water position from the cave ceiling. As a result, the minerals in the water deposit irregularly during the dripping process, eventually forming the curved stone that we see.