Here's an interesting article on modern day Egypt and the Nile in particular, written by an author on his recent travels along that river by train. Reading it helped link up some elements of the ATITD geography a little better in my mind.
The author also claims that Egypt for all intents and purposes is the Nile and adjoining land, and all the desert that the nation possesses going East and West from the Nile has little bearing on Egyptian culture. I think he just called the Tanis community a bunch of phonies. Let's kick his ass!
Much as I'd like to administer a beatdown Tanis-style … the dude's exactly on the nose. He's got us. Egypt is basically the Nile and the few miles of green land on either side of it. Ancient Egyptian culture was unique in many ways because of its unique geography. Not many societies could even dream of building titanic tombs and statues for their dead. The Egyptians could, because they had the biggest backyard in the entire ancient world.
And the Sinai peninsula, of which Tanis comprises the northern half, is basically all desert. When we first encamped on the lake in Tale 1, and I cast around for something to name it, the first thing I did was check online maps to see what the lake was called in real life. That's when I discovered that there IS no such lake in real life.