underground river

基本解释

Moving to the entrance of the underground river, I took a quick break and embraced the cold air and mists encircling me.
前往地下河入口的途中，我快速的休整了一下，拥抱了环绕我的冷冷的空气和雾气。
We found a spot where we could station, anchor and go down to the entrance to the underground river, avoiding a time-consuming passage across the thick forest.
我们找到了一个地点，在这里我们可以立足，固定锚点（anchor）然后向下攀爬到地下河的入口，从而避免耗时的穿过浓密的森林。
Beginning in a crystal clear lagoon at the mouth of a limestone karst cave on the Philippine island of Palawan, the Puerto Princesa Subterranean River is the world's largest underground river.
普林塞萨港地下河是世界上最大的地下河，它开源于菲律宾巴拉望岛上喀斯特石灰岩山洞口晶莹剔透的泻湖。

After the passage is over, Milton addresses Alpheus, a river god -the god who was noted for plunging the course of his river underground in order to chase the nymph Arethuse who had been turned into a fountain.
这段结束后，弥尔顿引用了河神阿尔甫斯,那位因私底下掀起河流的波浪而闻名的神,以此来与被变成海底之泉的女神阿托瑞萨相互融合。
耶鲁公开课 - 弥尔顿课程节选

It will include relaxation, group discussions, an underground river and plenty of group meals.
FORBES: Connect
The channels will not feed into the Yellow River, but will pass under the river in specially built underground channels.
NPR: River Has Long Reflected China's Glories, Sorrows