In this book, which is on the border between a novel and an anthology, Ursula K Le Guin transforms airports into the only areas in our world that allow travel to parallel universes. So that if you miss a flight or it is delayed, you can spend those dead hours getting to know other planes. She doesn't explain very well how or why, and perhaps I would have liked to know more about that, but she does perfectly describe all the cultures we will encounter in the different planes. In the form of stories of different people who have traveled to them, Ursula tells us what the topography, people, society, religion, and economy are like.
Don't expect a book with a plot, that's not what you'll find here. Instead, you'll find an overflowing display of the author's imagination, and in each chapter we can see Ursula's world-building ability. And also, of course, each chapter contains a reflection or a critique of our own world, talking about war, colonization, freedom, capitalism...
A hidden gem that I haven't heard much about, but that I recommend if you want to get to know the author better. A curious book that contains more than it seems at first glance.