Billed as a 'small' citadel, I think it's actually quite a spacious one, suitable for whatever political intrigues or bloody insurrections you may have in mind. The introductory material covers the customisation possible (showing or hiding fill, numbers, grid, and furniture) and presents a legend for map symbols - and also suggests that the grid be taken as 20' squares as the place is large! There are also some ideas for how the citadel can feature in your game. This might be the centre of a larger town, or a stand-alone and self-sufficient outpost. It's on a river (or sea shore) with a dock, as well as stables, a forge, inns, and other necessities.
The first plan shows ground level, the second shows the upper level, and the third the rooftops (perfect for parkour...). There are two further plans, one showing the caverns underneath, part of which has been altered to form a dungeon complete with cells, the other presents a sewer system.
There are well over an hundred rooms to play with. The temple is massive, either whoever rules here is quite fanatical about their deity or maybe this is the base of a religious rather than secular power. Although the introduction talks about stables, a forge, and drinking establishments, most of the chambers are able to be assigned as you wish - there are some obvious stables with rows of stalls.
The main courtyard boasts a massive structure which could be a flamboyant podium or memorial of some kind. Maybe this is where whoever is in charge holds audience, on dry days! There's accommodation, a cloister, halls, two entrances, and a smaller courtyard that has a gated entrance to the larger main one.
There's a lot to play with here. Have fun designing the centre of power for a faith or an area of your campaign world - or have even more fun gifting it to your party when they reach a resonable level or pull off an amazing feat that deserves reward, and watch them making it over as they wish (and then, of course, invade!). It's an unusual edifice, yet one replete with potential to do something quite unique!
[5 of 5 Stars!]