Hellmouth

In the northern part of my usual campaign region, there is a great — one might almost say grand, if one had no shame — canyon that penetrates in many areas right through to the Abyss.

It's like a summer camp for paladins, because all kinds of demonic critters crawl up out of there all the time.

That's it, in the centre-right of the map.

(You can see a much larger version of the map here — it's about 980KB).