The 3.0 Grey Citadel, also by Necromancer, is another one like that. I tend to get a lot of mileage out of many of Necromancers modules, like ToA, Durbenford, Rappan Athuk, Morrick Mansion, Amulet/Crucible, Bonegarden, and several others. The towns/cities/locations have all made good long term campaign fixtures. These adventures are not "fire and forget" adventures in a campaign. The locations and NPC's are great to have stick around to give your campaign continuity and depth.