I found three - Asi - Litani - Rasbani http://geology.com/world/Lebanon-satellite-image.shtml
The Jordan River is the/a key water source to Israel, Lebanon and Syria.
It was in Syria-Lebanon.
Syria
Syria-Lebanon, extending to Carthage in Tunisia and Carthaginia in Spain.
The Euphrates River
Syria and Lebanon both gained independence from France; Lebanon in 1943, and Syria, in 1946. French troops withdrew from Lebanon in 1946.
Syria and Israel http://bbsnews.net/bbsn_photos/topics/Maps-and-Charts/israel_lebanon_map.jpg
Syria and Israel theoretically share a border, but they are separated by the UNDOF forces which occupy a no-man's land between them. However, Syria and Israel both border Jordan and Lebanon. In the case of Lebanon, there is no land border with any nation other than Syria or Israel.
Lebanon is located in the middle east of Asia and is bordering the Mediterranean Sea, between Israel and Syria.
The countries that share international boundaries with Israel are Lebanon, Syria, Jordan, and Egypt.
Syria is bordered by Lebanon to the west, Turkey to the north, Iraq to the east, Jordan to the south, and Israel to the southwest.
Lebanon