South of the Old City, visitors to Jerusalem can enter a tunnel chipped from the bedrock by a Judean king 2,500 years ago and walk through knee-deep water under the Arab neighborhood of Silwan. Beginning this summer, a new passage will be open nearby: a sewer Jewish rebels are thought to have used to flee the Roman legions who destroyed the Jerusalem temple in 70 A.D.The sewer leads uphill, passing beneath the Old City walls before expelling visitors into sunlight next to the rectangular enclosure where the temple once stood, now home to the Al-Aqsa Mosque and the gold-capped Dome of the Rock.