Chand Baori
With no surveying instruments beyond simple tools, how did builders lay out roughly 3,500 steps in a repeating, symmetrical geometric pattern descending 13 storeys to the water table without a single visible error, and how much of what stands today is the original 8th-9th century core versus later rebuilding?
c. 8th-9th century CE · Abhaneri, Dausa District, Rajasthan, India