Archaeologists working on the restoration project of the "Domus Aurea" (Golden House), the vast palace of infamous Roman Emperor Nero, managed to uncover a hidden underground portion of the complex purely by accident, Science Alert reports.
According to the media outlet, the discovery was made when the team was working in one of the palace’s chambers and turned on the bright lights which shone into an opening in the corner, revealing "the entire barrel vault of a completely frescoed room".
The walls of the chamber are decorated with the depictions of mythical creatures such as centaurs and the goat-legged pagan deity Pan, as well as a "silent and solitary sphinx" for which the room was named.
"In the darkness for almost twenty centuries, the Sphinx Room ... tells us about the atmosphere from the years of the principality of Nero", Parco director Alfonsina Russo said as quoted by the media outlet.
While much of the chamber was still filled with dirt, archaeologists seemed reluctant to excavate it further due to concerns that such activities might destabilise the entire complex.