A highly sophisticated ancient water system dating back to the end of the Kingdom of Judah in the Seventh Century BCE and a Muslim structure from the Eighth or Ninth Century CE have been uncovered by Israeli, American and European archeologists at Kibbutz Ramat Rahel south of Jerusalem. Experts from Tel Aviv University, the University of Heidelberg and other academic institutions were involved in the dig. Its discoveries are said to have changed the known historical picture of Ramat Rahel, which turns out to have been a major royal site whose exact identity is not yet known. Tourism Minister Isaac Herzog, who visited the site on Monday, said the findings were among "the rarest and most important presented by Israeli archeology. The historical and archeological aspects of tourism in Israel have already proven themselves as a welcome natural resource whose proper exploitation can serve both domestic and foreign tourism." Herzog added that collaboration among universities and with the Antiquities Authority is vital for establishing a physical network based on historical tourism and making it attractive to tourists. The Tourism Ministry "will be happy to include the Ramat Rahel site in the relevant information campaign to stress historical attractions for people coming to Israel in general and Jerusalem in particular," Herzog said. Plans have not yet been announced for opening the site to the public. The water system, cut deep into the rock foundation, includes large underground water reservoirs, five open pools, small canals that transported water between the pools and three underground canals. The system continued to be functional, although with some alterations, during the Persian Era, the return to Zion after the destruction of the First Temple, the Fifth and Fourth Centuries BCE and through the Hellenistic Era in the Third Century BCE. Along with 18 Jewish ritual baths from the Hellenistic Period, the archeologists uncovered a bathhouse and villa, and a large Byzantine village with a church, monastery, rooms and halls. Dr. Oded Lifschits, who headed the dig on behalf of TAU, said that the system is "many branched and unparalleled in Eretz Yisrael archeology. So far, its aims and history are not clear. As water facilities from various historical periods - such as a Roman bathhouse and Hellenistic ritual baths - have been found at Ramat Rahel, it seems that water takes a central place in the history of the site and that it still bears many secrets," he said. The Muslim structure, from the period between 750 and 1000 CE, had its origins in the Byzantine Era and underwent changes. Various ceramic implements, candles, coins and facilities, such as an original water hole under a constructed arch, were found. The Ramat Rahel dig began in the summer of 2005 to investigate a number of principle questions such as the nature of the biblical-era citadel and the magnificent palace at a place that served as an administrative center during various important historical periods. Evidence for this is provided by a large collection of seals marked "The King," "Lion" and "Yehud." The current digging season is the second of five that are planned. Some experts claim the fortress - which has no parallel inside Jerusalem - was used by the kings of Judah, while others claim it dates back to the Assyrian Empire or to the Israelite kings who ruled for a certain period in Judah. Some 120 people, including students and volunteers from Argentina to Australia and North America to Indonesia, are taking part in the current dig. They arrived in July despite the war and will remain until the end of August. Many of the foreigners, aged up to 70, represent various types of expertise, from computer experts to Christian clergymen in European villages, who decided to devote their annual vacation to Israeli archeology. Ramat Rahel, located four kilometers south of the Old City of Jerusalem, was first dug by Prof. Y. Aharoni in the 1950s and 1960s. When the reservoir of the kibbutz was first built in the Fifties, remnants of the ancient settlement were discovered.