I read this book Septimus today. It's about a modern British school boy who is magically transported from a museum back to the ancient Roman Empire. He is imprisoned for calling Nero fat, and as a punishment is sent to the underworld to complete seven labors, in which he learns much about ancient Rome and about himself. Now, I think the concept of being magically transported to a fantastic realm naturally invites comparisons with Harry Potter, and it can be safely recommended to all fans of the boy wizard.

https://archive.org/details/septimus-a-first-latin-reader