Some of the greatest feats of engineering began a millennia or two ago with structures such as the Great Pyramids, the Hanging Gardens of Babylon, and the Roman Colosseum among others.
Rome is one of the ancient civilizations that paved the way for us to have the knowledge of building roads, bridges, aqueducts, and all sorts of infrastructure.
One such edifice is the Archbasilica of St. John Lateran:
The basilica, where the Pope presides in his role as Archbishop of Rome, was already ancient when it was rebuilt in the 1650s. Its walls still hold some of the original material used to build the cathedral under Emperor Constantine in 312 CE.
And beneath the modern church lies the original Roman foundation. Excavations since the 1700s have opened up a network of dark, cramped spaces called scavi beneath the four-hectare site of the cathedral.
After years of excavation and research, archaeologists have now been able to map out the various structures within and beneath the cathedral using laser scanning and ground penetrating radar technology.
(Image credit: Lateran Project/Newcastle University)