The Pantheon is amazingly well-preserved compared to the other ancient ruins in Rome. (For many of the ancient sites, I hear Indiana Jones’ voice in my head muttering “the general poor condition of the find.”)
The secret of its preservation is that it the building has been continuously used since it was built. First as a pagan temple, then as a Christian church.
The building and the light made the whole thing seem almost like CGI.
Marble everywhere.
Presumably — at the right time of day — this shaft of light will show you the exact location of the Ark of the Covenant.