Triastu. The City of the Three. The Hallowed City. Triastu is the holy city of Trianarianism, and is the home of the Trirex. Many have paid homage to it, and many have gone on pilgrimages to it, and have marveled in its beauty.
Sid and Jir were childhood friends growing up in the same town on the ocean. Both creative geniuses, both with the need to be better than the other. Many will tell you that this friendship created their genius while others realized, in hindsight, that it spelled the lands doom.
It looks like a cook's book. It is a cook's book. It is also where the cook, who happened to be a master spy, encoded all his secrets and contacts. The book has innocently fallen into your group's hands. Everyone wants it, and many are not subtle or peaceful in their attempts.