Amberground aka AG is the world in which Tegami Bachi takes place. The entire country of Amberground has no sun, with the only light coming from the man-made sun that rests over the capital, Akatsuki. The country of Amberground is surrounded by water on all sides and is split into three regions and class, with the brightest and the capital region being in the middle. Massive ring-shaped lakes separate the three regions and they can only be crossed if you take one of the bridges. To cross the bridges, you need to have a crossing pass, which allows you to cross between the regions. Crossing passes are acquired through hard work, and the government has gates and gatekeepers to regulate who goes where. It is almost impossible to gain a crossing pass if you are a normal citizen. Bees have access to a crossing pass.