As per DU's idea, I'm running a second Dawnlands game for those interested in a more old-school feeling. We'll use one of Iron Heroes, Labyrinth Lord, or OSRIC. PCs should be any race in those games - other races from the 4e will be for NPCs unless someone _really_ wants to play them, and if they do, we'll cook up a conversion.
PCs ought to be explorers and adventurers interested in the Giant's Grave:
Giant's Grave
One of the more peculiar landmarks that a traveler in the south-western plains can navigate by is Giant's Grave. It is the incomplete burial site of some long dead titan, though why it is incomplete is unknown. A great chasm opens in the earth, plunging down for hundreds of feet into near-blackness. On a bright day, the faintest of light makes it way down and a massive humanoid skeleton can just barely be seen. A single great mound of earth runs the length of the chasm on the western side, though it's now pockmarked with warrens and tunnels for all sorts of beasts that live in the darkness.