A spectacular underground quarry has recently been discovered in the Jordan Valley north of Jericho, which archaeologists believe may have marked a biblical site sacred to ancient Christians.

The large cave was discovered by Prof. Adam Zertal and a team from the University of Haifa which has been conducting a survey of the region since 1978. "When we reached the entrance to the cave, two Bedouin approached us and warned us not to go in, because it was cursed and inhabited by wolves and hyenas," Zertal said yesterday from the site.

They entered anyway, discovering a ceiling supported by 22 gigantic columns on which various symbols were carved, including 31 crosses, a possible wheel of the Zodiac and a Roman legionary symbol. The columns also had niches for the placement of oil lamps and holes that apparently served as hitching posts.

Zertal says their working theory is that the site is Galgala, biblical Gilgal, mentioned on the sixth-century Madaba mosaic map. The cave, buried 10 meters underground, is about 100 meters long, 40 meters wide and 4 meters high, is the largest artificial cave so far discovered in Israel.

Potsherds found in the cave and the carvings on the columns led Zertal to date the first quarrying of the cave to around the beginning of the Common Era. It was used mainly as a quarry for 400 to 500 years," but other finds give the impression it was used for other purposes, perhaps a monastery or even a hiding place," Zertal said.

Zertal said scholars wondered why people would dig a quarry underground considering the effort needed to just to pull the stones out of the ground.

A possible answer may be in the famous Madaba Map of ancient Palestine, found in Jordan. In it, a place named Galgala is marked and an accompanying Greek word meaning "12 stones." The map also depicts a church near the site. Archaeologists say they have found two ancient churches near the cave.

According to Zertal, scholars had always assumed that "12 stones" refered to the biblical story of the 12 stones the Israelites set up at Gilgal after they crossed the Jordan. However, the discovery of the quarried cave may mean the reference was to a quarry established where the Byzantines identified Gilgal. Zertal explains that in antiquity sanctuaries were built out of stones from sacred places.

If the Byzantines identified the site as biblical Gilgal, it would have been considered sacred and quarrying would have remained underground to preserve it.