The video features archaeologist Darius Arya taking viewers on a tour of the secret rooms of the Pantheon in Rome. The Pantheon is one of the best-preserved ancient Roman temples, known for its famous front porch and impressive Rotunda with the largest unreinforced concrete dome weighing about 5,000 tons.

However, there are also hidden spaces within the Pantheon, including the Graton, which is a structure constructed to sustain the Rotunda. The Graton consists of radial walls that buttress up the southern side of the Rotunda and is encased in a brick structure.

Arya takes viewers inside the Graton and shows the 7th Century icon dedicated by Pope Bonfice IV to the mother of God, Panaga Hria. Additionally, he shows the Basilica of Neptune, which is a massive structure with a Monumental app that was rebuilt after a fire in 110 AD.

The structure was attributed ultimately to Hadrian, but originally there was the Stow of Neptune in the time of Augustus built by Agria. Arya highlights the architectural features of the Pantheon, including relieving arches that are inserted in the fabric of the walls. The video offers an opportunity to explore the lesser-known aspects of the Pantheon and the history of ancient Rome.