D&D 5E If you've run Keep on the Borderlands (in any edition)...

[Sailor Moon]

I just want to say I absolutely love this adventure. I can't tell you how many times we have used the area as a basis for several campaigns through the years.

 

[Henry]

I just want to say I absolutely love this adventure. I can't tell you how many times we have used the area as a basis for several campaigns through the years.

Yeah, me too. Between this and "Horror on the Hill" i've probably run them each a half dozen times over the last 30 years. Every time i've run it though, it's never come up - either the party never reached that far or i just left it caved in because the group had had their fill of the caves by then and didn't want to explore an area for which the only exit might be caved in and trap them in the future.

 

[ExploderWizard]

Oh, interesting. In "Return," it's actually labeled as a passageway to Quasqueton. And the cave-in's gone.

I was wondering why the idea was stuck so firmly in my mind...

Although that said, the thing marked on the map (and to which the tunnel leads) is actually only a barrow that contains the entry to a passageway leading to Quasqueton, not Quasqueton itself. And that passage is still blocked by rocks.

Yeesh.

Last time I ran this, I had the passage just lead to the barrow and that was it. It was simply a back door into the shrine.

 

[Olgar Shiverstone]

I've run it with it leading to B1 (way, way back in the day), but I think a better solution is that it leads to the Underdark. It's so nasty down there that even the humanoids want it blocked. But if you're party is determined enough, they can clear the rubble and descend into the depths ...

 

[steeldragons]

I've run it with it leading to B1 (way, way back in the day), but I think a better solution is that it leads to the Underdark. It's so nasty down there that even the humanoids want it blocked. But if you're party is determined enough, they can clear the rubble and descend into the depths ...

I was going to say something similar. Depending on how mutable your world geography is at the moment, you can have it lead anywhere! Going down into the underdark to start "Descent", bypass/skip the wilderness part and have it join straight into somewhere in the Lost Caverns of Tsojcanth, the underground mines/slave pens of the Slavers, etc...

Now, given that the party coming from the Caves of Chaos would likely be a lower leveled party, you could come out on the other side of the "mountains/rocky terrain" to open to a coast and look down over a broad plain to a little sleepy coastal village named Saltmarsh, still inland but see the village of Hommlet below, the farming fields and winding road that takes them to Orlane (and the Cult of the Reptile God) or (more geographically possible) it opens out into the hilly region where one might find/explore the environs of Bone Hill.

The possibilities really are endless.

 

[Grimstaff]

...what, if anything, did you decide is down the long, rock-filled passage??)

I thought it was common knowledge this tunnel leads to the Inverted Bleeding Pyramid of the Yaun-Ti God?

 

[catenwolde]

The first time I ran it (WAY back when) I used the tunnel as the secret entrance for the evil cleric in the Keep, who was the mastermind behind the gathering of the goblinoid and undead armies - that actually worked out pretty well, allowing me to play off the conspiracy elements a bit better I've also just used it as a home-made expansion for the Temple after rewriting that complex a bit (i.e. the written part was the fore-temple, the home-made part the Real Temple with an even Bigger Bad), and later I just linked it to a re-written B1 on the hill as an outpost of the Temple. I'm currently trying to think of reasons & means to have it link to the Caverns of Thracia (perhaps the Temple's whole purpose for gathering at the Caves is to try to find and explore the Caverns of Thracia, looking for the Foozle of Doom).

This is a great example of how extremely minimalist scenario elements ("it's a tunnel ... to where?") can be used as great creative levers in a well designed sandbox.

 

[Olgar Shiverstone]

Perhaps it also connects to a tunnel complex that leads to the Great Underground Empire (keep torches lit) of Cynidecia, which further lies on the inside surface of the sphere that is the Hollow Earth.