Zedekiah's Cave

Zedekiah's Cave, also known as Solomon's Quarries, is a 5-acre (20, 000 m2) underground meleke limestone quarry under the Muslim Quarter of the Old City of Jerusalem that runs the length of five city blocks, named after King Zedekiah (Tzidkiyahu, a Judean king of the 6th century BC). It was carved over a period of several thousand years and is a remnant of the largest quarry in Jerusalem.

Cave data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).