Besides enjoying the steam that rolls with the mountain mist over the land and squinting when the acidity stings your eyes, you will perhaps sometimes hear a sound that resembles water boiling in a tea pot. It's coming from the mud bubbling by the side of your feet. These holes are called marl cauldrons, and sulfur gas is responsible once again.
除了感受隨著山嵐滾動如湧浪變化的蒸汽，及不時要眯一眯被強酸刺痛的眼睛以外，你可能還會聽到一種類似壺中開水沸騰的咕嚕聲，就在你的腳邊一個個冒氣泡的泥洞，別懷疑，它也是硫氣活動的一種，叫做「灰泥洞」。