This is rather neat: a complete location, fully populated and replete with details and backstory, all ready for you to drop into a campaign and use as an adventure location. Although a few adventure ideas are given in case you don't have a ready reason for your party to go there, it isn't an adventure per se, it's a place in which adventure could happen and that adventure is up to you.
Basically it's a troglodyte lair, described in loving detail. The denizens all have their own lives, their own reasons for being here and their own plans and hopes for the future. This gives the feel of a location that's existing in your alternate reality irrespective of what the characters get up to, you get the feeling that the troglodytes will continue on their merry way even if the party never stops by at all. Yet if they do, it isn't a place that has sprung into existence just to provide them with a good brawl and something to loot, it's there already and they have just chosen to visit - something that serves to enhance the 'reality' of your campaign setting.
The whole place is well laid out and explained clearly, with 'read aloud' descriptions and all the information you need to manage events when the party arrives at each location. There's a good map - spread over two pages - and a new deity as well - and a deity who teaches that 'Anything stolen is rightfully yours if you are not seen taking it' has a certain appeal, possibly beyond troglodytes!
This is a nice resource to have, a traditional 'crawl ready to use whenever it fits in with the rest of your plots.