Chinas biggest ice cave is located in the northern province of Shanxi. At an altitude of 2，300 meters， the cave is more than 100 meters deep. It was formed around three million years ago.

The cave， in the Luya mountain in Ningwu County， Xinzhou City， is connected with Fenhe River， which is believed to provide water for the cave.

The cave is less that half an hours drive away from the headstream of Fenhe River. Once， as an experiment， a haystack was placed at the bottom of the cave and it disappeared， only to be found the next day in the river.

Scientists are still researching how the cave formed. Such caves are normally found in extremely cold areas such as Antarctica or Siberia， but Luya mountain is at a similar latitude to Lisbon in Portugal.

During World War II， war horses that were killed during fighting were stored in the cave， as the sub-zero temperature ensured the meat would keep and it could be eaten at a later time.

The wooden ladders in the cave are cleaned twice a day， otherwise they would collect layers up layers of ice. Because the ice continues to form， the ice cave changes all the time.

The cave is open for visitors from April to October each year， when a maximum of 3，000 people are allowed to enter daily.

In the past， villagers used the ice from the cave for medicinal purposes. However， to protect the cave， such behavior is now banned.

中國最大的冰洞位于北方的山西省。該冰洞海拔2300米，洞深100多米，是約300萬年前形成的。

這座位于忻州市寧武縣蘆芽山的冰洞與汾河相連，人們認(rèn)為是汾河為冰洞提供了水源。

該冰洞距汾河的發(fā)源地不到半小時(shí)的車程。有一次，作為一個(gè)實(shí)驗(yàn)，一個(gè)被放置在冰洞底部的草垛消失了，第二天卻在汾河被發(fā)現(xiàn)了。

科學(xué)家們?nèi)栽谘芯吭摱囱ㄊ侨绾涡纬傻?。這樣的洞穴通常出現(xiàn)在極寒地區(qū)，如南極洲或西伯利亞，但蘆芽山和葡萄牙里斯本的緯度相近。

二戰(zhàn)期間，在戰(zhàn)斗中被打死的戰(zhàn)馬就存放在冰洞里，因?yàn)榱銛z氏度以下的溫度能確保肉類保存完好，并且以后也可以食用。

洞里的木梯需每天清掃兩次，否則將積起層層冰層。因?yàn)楸浅掷m(xù)形成的，所以冰洞時(shí)刻都在變化。

冰洞每年4月至10月對(duì)游客開放，每天最多允許3000人進(jìn)入。

過去，村民使用冰洞里的冰做藥用。但是為了保護(hù)洞穴，這樣的行為已被禁止。

Word Study

headstream /'hedstri?m/ n. 源頭；源流

Ocean culture is one headstream of whole mankind culture， showing peoples history and creativity.

ensure /?n'???（r）/ v. 確保；保證

Please ensure that all lights are switched off.

layer /'le??（r）/ n. 層；層次

A thin layer of dust covered everything.endprint