9/10 - I was so happy to get back to this genre. Back in the day, all I used to read was Anne Rice novels ;-) This book had the added bonus of making me feel like a world traveler, or desperately wanting to be one. I found myself looking up Hagia Sophia and other sights from the book on the internet. I really enjoyed the author's writing style and the letter format was very effective in telling the story. The suspense was just enought to keep you moving through all 700 pages. And the historical perspective was very interesting, and sometimes horrorifying (please no more mention of babes being impaled while still at their mother's breast!). I would recommend it, although it definitely takes a patient reader. It's not a fast read, but meant to be lingered over.