Modern descriptions are woven in with the ancient ones. The underground trains of Zirma are mentioned, when trains did not exist until 500 years after Marco Polo. That is the first clue that this book means to transcend time, to travel back and forth through it without regard. Sophronia has a rollercoaster, carousel, Ferris wheel, motorcycles, and factories — all of which were, obviously, never encountered by Marco Polo. Leonia, a city with refrigerators, radio, toothpaste, and light bulbs— is a city that sounds like the whole of America.
I find myself wishing there was a videogame with the objectives of building and maintaining the cites described in this book. Something along the lines of Sid Meier's Civilization series, or the Anno games, or even another version of The Sims and Sim City would be wonderful to bring this book to life.