Beste and his colleagues spent four years using measuring tapes, plumb lines, spirit levels and generous quantities of paper and pencils to produce technical drawings of the entire hypogeum. “Today we’d probably use a laser scanner for this work, but if we did, we’d miss the fuller understanding that old-fashioned draftsmanship with pencil and paper gives you,” Beste says. “When you do this slow, stubborn drawing, you’re so focused that what you see goes deep into the brain. Gradually, as you work, the image of how things were takes shape in your subconscious.”
https://www.smithsonianmag.com/history/secrets-of-the-colosseum-75827047/