From publisher blurb:
Finally back to town after a hard day's tunnel hacking (or swamp-slogging)? Well, there might be a bit more going on than you expect. Lowhollow isn’t the sprawling, kingdom-sized area of urban settlement that Pholus and Estvol are, but it has a sizeable population bolstered by land and seafaring trade routes.
Have as much adventure in the city as out in the wilds. Delvers in Lowhollow explore not only the dingy side of the city, but the consequences of getting caught. If you get too careless while you're dreaming of the riches of the harbor district, you could very well end up working the Pitt.
This is an adventure setting for common kindred delvers of levels 3 to 5 using 7.5 edition rules, although it is easy to modify for 5th and other editions.