Rome authorities this month opened a new archaeological park and museum in the shadow of the Colosseum that features an original marble map of Ancient Rome that visitors can literally walk over.

Researchers have used ground-penetrating radar to map an entire ancient Roman city, detecting remarkable details of buildings still deep underground including a temple and a unique public monument.

Concealed for decades, a huge network of chambers beneath Rome’s Capitoline Hill is to be opened up to the public, revealing a forgotten chapter in the city’s ancient history.