Climate
The temperature in the caves is about 16°C all year round.
History
Caverns sculpted by water and time.
Few caverns in the world approach the astounding wealth or the extent of those of Jeita.In these caves and galleries, known to man since Paleolithic times, the action of water has created cathedral-like vaults beneath the wooded hills of Mount Lebanon.
The modern discovery of the underground river of Jeita dates to 1836 and is attributed to Reverend William Thomson, an American missionary who ventured some 50 metres into the cave. Reaching the underground river, he fired a shot from his gun and the resulting echoes convinced him that he had found a cavern of major importance.
In 1873 W.J. Maxwell and H.G. Huxley, engineers with the Beirut Water Company, and theirfriend Reverend Daniel Bliss, president of the Syrian Protestant College later the AmericanUniversity of Beirut explored these caverns. In two expeditions carried out in 1873 and 1874 they penetrated 1,060 metres into the grotto-principal source of the Nahr el-Kalb thatsupplies Beirut with water. They were finally stopped by "Hell's Rapids", where the riverflows in torrents over razor sharp rocks.
Like explorers everywhere, Dr. Bliss, Mr. Maxwell and the other engineers could not resistrecording their names and the year on "Maxwell's Column", a great limestone pillar some 625 metres from the entrance.
About 200 metres further on, in the so-called "Pantheon', they wrote their names and details of the expedition on paper, sealed it in a bottle and placed it on top of a stalagmite. The action of the lime- impregnated water has since covered the bottle with a thin white film, permanently fixing it to the stone. Between 1892 and 1940 further expeditions werecarried out, mostly by English, American or French explorers. These efforts brought them to a depth of 1,750 metres.
Since the 1940's, Lebanese explorers, notably the members of the Speleo-Club of Lebanonfounded by the first Lebanese speleologist Lionel Ghorra, have pushed even deeper into the Jeita grotto. Their methodical exploration revealed the great underground system of the upper and lower galleries which is now known to a depth approaching 9 kilometres.
The upper galleries, discovered in August 1958 by Lebanese speleologists, required a hazardousclimb to 650 metres above the entrance of the underground river. Altogether, 2,130 metres ofthis gallery have been explored.