The Pantheon in Rome is a true architectural wonder. Described as the “sphinx of the Campus Martius”—referring to enigmas presented by its appearance and history, and to the location in Rome where it was built—to visit it today is to be almost transported back to the Roman Empire itself.

Most textbooks and websites confidently date the building to the Emperor Hadrian’s reign and describe its purpose as a temple to all the gods (from the Greek, pan = all, theos = gods), but some scholars now argue that these details are wrong and that our knowledge of other aspects of the building’s origin, construction, and meaning is less certain than we had thought.