This is the observatory of Maj'Dul. Inside you will find NPCs that can advance your Court factions when you turn in tokens to them. Also there is a book binder that can re-bind the books and pages you find throughout Desert of Flames.
The information below has been verified with in-game data and the information on this page is correct, even if it looks stupid or makes no sense.Fact: The zone is called "The Tower of the Moon"