Series description from the Living Greyhawk website:
"For the last two years, Living Greyhawk's core plot arc has focused on the Bright Lands and the machinations of the Archmage Rary. Now, with that series drawing to an end, we can finally reveal exciting information about next year's plot arc: Greyhawk Ruins. The arc consists of four adventures designed to complement the super-adventure Expedition to the Ruins of Greyhawk by Jason Bulmahn, James Jacobs, and Erik Mona set in the Free City itself, the ruins of Castle Greyhawk, and the dungeons below.
These are adventures with a twist, though. Traditionally, Living Greyhawk adventures are one-round or, rarely, two-round affairs. The dungeons below Castle Greyhawk, though, are far too extensive to be detailed in the traditional three or four encounters featured in such adventures. Thus, each Greyhawk Ruins adventure will contain as much challenge as four, one-round adventures. Playable in one, two, three, or even four sessions, each adventure explores some of the more easily accessible dungeon levels and other as yet secret locations."
This series comprises
CGR7-01 Ruins of Discovery
CGR7-02 The Silent Barracks (aka Into the Silent Halls)
CGR8-01 Crypts of the Forgotten
ADP8-03 Expedition to the Ruins of Greyhawk (Expedition to the Ruins of Greyhawk was required to play these adventures)