Photo: The Canadian Press

Israeli archaeologists on Monday announced the discovery of the first known Roman-era theatre in Jerusalem's Old City, a unique structure around 1,800 years old that abuts the Western Wall and may have been built during Roman Emperor Hadrian's reign.

The edifice's elegant masonry was found during excavations carried out in the past two years below the Western Wall tunnels, a warren of ancient subterranean passageways running alongside a contested Jerusalem holy site built by King Herod in the first century B.C. The excavations exposed eight previously uncovered courses of the Temple Mount's western retaining wall.

Jews consider the Temple Mount the holiest site on earth, while Muslims refer to the walled compound as the Noble Sanctuary and consider it the third holiest after Mecca and Medina. It was the site of two Jewish temples in antiquity — the second renovated and expanded by Herod — and today is home to the Al-Aqsa Mosque and Dome of the Rock.

Joe Uziel, an Israel Antiquities Authority archaeologist heading the dig, said that the theatre-like structure is believed to date to the second or third centuries — the period after Rome razed the city in 70 and the Emperor Hadrian rebuilt it in the mid-second century as a Roman colony, Aelia Capitolina.