A team of archaeologists, architects and computer scientists have scanned, in full 3D, all 170km of the Catacombs under Rome.
You can travel “through” walls, down corridors and into chambers, giving the first real sense of its beauty, scale and detail.
Paintings on walls, which have not been seen in nearly 2,000 years, are now visible – their colours vivid and clear.
“It is not a virtual image, it is not animation – what you are seeing is real data,” says Mr Zimmerman.
The article also contains some sample video.