Built in Rome around 126 AD, the Pantheon's dome spans roughly 43 metres and remains the largest dome of unreinforced concrete ever constructed, nearly two millennia later. Its design, including a central oculus that lets in light and rain, has influenced domed buildings ever since.
Record no. MRB-2026-005685
World's Largest Unreinforced Concrete Dome
Reference Record – Not Certified
This record is compiled from publicly available sources for reference. It has not been examined or certified by The Book of World Records.