From the publisher's website:
The "El Raja Key Archive" is an interactive, searchable, fully indexed, virtual museum of roleplaying game artifacts from the dawn of the Dungeons & Dragons game!
Contained within the Archive are over 1,000 high-resolution scans of adventures, maps and keys, campaign notes, character sheets, and manuscripts from the Original Greyhawk, Kalibruhn, and Blackmoor Campaigns - from the very creation of Dungeons & Dragons!
Includes all maps and some keys for Rob Kuntz's Castle El Raja Key, the dungeons where Gary Gygax cut his teeth as Mordenkainen; Rob's manuscript for his lost Dungeons & Dragons Supplement V: Kalibruhn; maps, keys, and notes for over 40 adventures from the Original Greyhawk and Kalibruhn Campaigns including, maps & some keys for 16 of Rob's Original Greyhawk Castle levels, the map for the first ever D&D demo, the Machine Level, at GenCon VII in 1974, and the map for the first ever D&D tournament, Sunken City, and notes, NPC cards, and adventure maps and keys for the Original City of Greyhawk!
Along with the high resolution images of these treasures is extensive historical commentary that is fully linked to our searchable index. The El Raja Key Archive uses your internet browser interface to navigate. It can be used on virtually any computer that has a internet browser.