The hole in the top of the pantheon was to let in light and air.
Pantheon rome hole in roof rain.
Open roof in the rain see 78 054 traveler reviews 36 872 candid photos and great deals for rome italy at tripadvisor.
And at least partially to let out smoke from candles lamps and torches you have to remember that at the time the pantheon was.
The pantheon rome 8 31 smarthistory upon entry visitors are greeted by an enormous rounded room covered by the dome.
Obviously being open to the elements means it also rains inside the pantheon but a gently sloping floor and 22 well hidden holes help the water to drain away.
It was explained to me that the hole in the pantheon is an optical illusion that is to say while standing inside it appears to be level parallel with the ground when it fact it is built at a steep angle thereby allowing light to come in normally but making it more difficult for rain to fall in.
Actually it s not covered because a roof could deteriorate the internal structure of the building.
Anyway the whole area isn t dameged by the rain they keep the situation under control and.
The oculus at the top of the dome was never covered allowing rainfall through the ceiling and onto the floor.