Beneath Jerusalem, an underground city takes shape

In a multilevel maze of rooms and corridors beneath the Muslim Quarter, workers cleared rubble and installed steel safety braces to shore up crumbling 700-year-old Mamluk-era arches.

Above ground, a group of French tourists emerged from a dark passage they had entered an hour earlier in the Jewish Quarter and found themselves among Arab shops on the Via Dolorosa, the traditional route Jesus took to his crucifixion.

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.

From there, it's a short walk to a third passage, the Western Wall tunnel, which continues north from the Jewish holy site past stones cut by masons working for King Herod and an ancient water system. Visitors emerge near the entrance to an ancient quarry called Zedekiah's Cave that descends under the Muslim Quarter.

The next major project, according to the Israel Antiquities Authority, will follow the course of one of the city's main Roman-era streets underneath the prayer plaza at the Western Wall. This route, scheduled for completion in three years, will link up with the Western Wall tunnel.