A good chunk of the limestone used to build the city above came from this 9000-sq-metre underground cavern. Used on and off from the Second Temple period to the 16th century, it was rediscovered in 1854 by American missionary James Barclay, with the help of his dog. Freemasons, who continue to hold meetings here, believe it was the source of stone used for Solomon's Temple. Others think treasures are waiting to be revealed. It's just north of Damascus Gate.
Scars from centuries of chipping away at the relatively soft rock are easily visible on the walls and ceiling – 50m of stone separate the roof of the cave from the Old City homes above. The space is warm and extremely humid, and a stream drips from the ceiling, said to have provided running water for 1000-plus years. The source is unknown, but legend says it's the tears of King Zedekiah, the last king of First Temple–period Judea, who was captured by the Chaldeans trying to flee through the cave after the Temple was destroyed.
Check out the graffiti signature of Baruch Kantinka, the architect of the Jerusalem YMCA and a Freemason.
Concerts with well-known Israeli musicians are held here every few weeks – it's certainly one of the most atmospheric places to hear live music in the city. Occasional treasure hunting games for kids are held here too.