JERUSALEM, June 21 (Reuters) - Israeli archaeologists said on Sunday they had discovered the largest underground quarry in the Holy Land, dating back to the time of Jesus and containing Christian symbols etched into the walls.

The 4,000-square-metre (yard) cavern, buried 10 metres beneath the desert near the ancient West Bank city of Jericho, was dug about 2,000 years ago and was in use for about half a millennium, archaeologist Adam Zertal said.

The cave's main hall, about three metres tall, is supported by some 20 stone pillars and has a variety of symbols etched into the walls, including crosses dating back to about AD 350 and Roman legionary emblems.

Zertal said his team from Haifa University first discovered the site three months ago while they were putting together a detailed archaeological map of the area.

We saw a hole in the ground ... and went down and discovered this giant cavern, originally a quarry, built uniquely with hall after hall, Zertal told Reuters.

The team believes the stones were used in buildings and churches in the region, but Zertal said further research was necessary.

The site may eventually be turned into one of the largest underground tourist sites in the Holy Land, he said.
(Writing by Ari Rabinovitch; Editing by Michael Roddy)