* '''Published:''' August 1990 * '''Publisher:''' TSR * '''Author:''' Aaron Allston * '''Format:''' boxed set * '''Rules:''' Classic D&D * '''Product:''' * [[http://rpggeek.com/rpgitem/46967/hollow-world-campaign-set|RPG Geek]] * [[http://index.rpg.net/display-entry.phtml?mainid=5005|RPG Net]] * [[http://tomeoftreasures.com/tot_dnd/hollowworld/hollowworldsetting.htm|Tome of Treasures]] * [[http://tsr.bothgunsblazing.com/hw/hw-box.htm|TSR Archive]] * [[wp>Hollow World Campaign Set|Wikipedia]] * '''Review:''' * [[http://grognardia.blogspot.co.uk/2009/08/retrospective-hollow-world-campaign-set.html|Grognardia]] * [[http://www.legrog.org/jeux/donjons-et-dragons/hollow-world/hollow-world-campaign-set-en|LeGrog]] (in French) * [[http://prehistoricpulp.blogspot.co.uk/2007/08/dungeons-dragons-hollow-world-by-aaron.html|Prehistoric Pulp]]
* A 128-page Dungeon Master's Sourcebook, with everything the DM needs to run an exciting campaign in the Hollow World. Also in this book are extensive entries on all the Immortals represented in the Hollow World: their interests, their allies, their enemies. * A 64-page Player's Book, including how-to's for creating a native Hollow World character and ways to bring a Known World character into the Hollow World. Included in this are new spells specifically for the Hollow World. * A 32-page Adventure Book, containing several starter adventures and entries on the various monsters found in the Hollow World. * Four full-size, full-colour map sheets, showing the Known World and the Hollow World, and detailing the central, most populous areas of the Hollow World. * Ways and means to adapt this material to the Advanced Dungeons & Dragons 2nd Edition game!