Pantheon

The Pantheon still carries the largest unreinforced concrete dome in the world, 43 metres across and exactly as high, open to the sky through a nine-metre oculus. Hadrian rebuilt it around 126 CE and left Agrippa's name on the front.

Overview

The dome works because it gets lighter as it rises: thick travertine concrete at the base, light volcanic pumice at the crown, coffered to remove weight that carries nothing. The floor slopes gently to drains under the oculus, because the rain comes straight in and always has. It survived intact where every other temple in Rome did not, because it was given to the church in 609 and has been in use ever since; Raphael is buried inside.

Highlights

Stand under the oculus at midday and then again in late afternoon — the disc of light moves down the wall and across the floor, which is the building’s actual mechanism. Entry has been ticketed since 2023 and the queue moves quickly. Mass is still said here, and the interior is quietest immediately after it.

Overview

Highlights

Location