The Pantheon, built around 2,000 years ago during the reign of Augustus, is one of the greatest architectural achievements of ancient Rome. Its vast dome features a central oculus that allows light and rain to enter the interior. Far from being a flaw, the Romans devised an ingenious drainage system: the floor, designed as a perfect circle with its center subtly elevated, directed rainwater outward toward the perimeter. There, a series of discreet drains carried the water to exterior outlets, pr