Having completed The Book of the New Sun by Gene Wolfe a few weeks back, I promptly turned my attention to the sequel, The Urth of the New Sun. Set ten years after the events of the original series, it tells the story Severian's effort to fulfil the prophecy of the New Sun and the ultimate fate of Urth.
The Urth of the New Sun begins with Severian onboard the spaceship, Tzadkiel, on a journey to Yesod, a higher universe, where he, like several Autarchs before him, will undergo a test to determine if the people of Urth are worthy to receive the New Sun. There are, of course, mishaps and even an attempted mutiny along the way, as there are many who do not wish Severian to succeed. After all, the arrival of the New Sun will bring with it, a great cataclysm and most people of Urth will not survive. Soon after his arrival, Severian learns that there is no test and that he is the one to bring the New Sun. He then returns to Urth to prepare it as best as he can. However, this where things start to get a bit chaotic. Severian finds that he can travel the "corridors of time", sometimes at will, other times unconsciously. Indeed, when he arrives back at Urth, he is in the past, during the reign of the Monarch Typhon. Later he arrives at a time a few decades after he left, his wife sits on the throne of the Commonwealth and the New Sun is just about to arrive. Still later, he returns to the distant past to the time of Apu-Punchau, an ancient ruler in prehistoric Urth and then, finally, to a future time, a few generations after the return of the New Sun.
I must confess, I found the latter third of this book a bit difficult to follow at times, largely because of the time travel. Some of the journey's through the corridors of time were not made immediately known to the reader. Still, once I realized what had happened, I was able, with an occasional bit of rereading, to clarify things. All, I can really say as far as a recommendation is, if you enjoyed The Book of the New Sun, you must read The Urth of the New Sun. It doesn't tie up many loose ends from the original series (my sense is that Wolfe is not the kind of writer who feels compelled to do so), but it will answer the one big unanswered question, namely, what would become of Urth and the prophecy of the New Sun.