Could someone please spoil Keep on the Borderlands for me? What makes it iconic? I didn't get into D&D until late 2e - Skills & Powers era. My first module was the frikkin' Night Below.
To elaborate, Gygax provided a setting that had real flavour but required the DM to bring to life. It was essentially a mini-sandbox, with the intention that the DM add additional adventuring areas to it as well as expand the map. The Caves of the Unknown were shown on the wilderness map, and linked to the Caves of Chaos, but it was up to the DM to decide exactly what was there, using the CoC as a guideline.
The Caves of Chaos were just cool. In fact, I would say that the CoC map is easily one of the best TSR ever produced, if not the best. The areas were interconnected, allowing PCs to range freely over a wide range of encounters.
The Caves essentially were humanoid tribes, but the tribes were given character enough (Bree-Yark! for the kobolds; the bugbears' invitation to dinner [which took in my 3e players!]) to allow the DM to really bring them to life. Some of the encounters were iconic.....anything with an owlbear in it is good, IMHO. The evil clerics are fun, too, depending upon how much personality the DM wishes to give them. Certainly, they are the "Chaos" that the Caves are named for, and probably drew all those monsters to the caves in the first place.
As written, KotB can easily provide 6-8 sessions worth of adventuring, and, should the GM expand the region, it can easily be the focus for an entire campaign.
Plus, in addition to Gygaxian prose, there are Gygaxian staging tips, and a glossary!
There is a reason that 4e opened with "Keep on the Shadowfell".......and that was a hope to harken back to "The Keep on the Borderlands". Unfortunately, KotS fails in comparison. IMHO, of course. YMMV.
RC