The name "Rainbow Vale" was coined by Henriki Ardand, while Rigodruok is the name by which the natives know it.
Dragon #230 hints that Rigodruok was created by Zagig Yragerne long before his apotheosis. The Mad Archmage hid one of the Orbs of Dragonkind there in 361 CY, or conceivably in another valley with a similar location and description.
Sormod. a merchant-adventurer from Perrenland, came into the possession of a scrap of parchment originally recovered from Blackmoor Castle. The parchment included directions to the Rainbow Vale, and Sormod set off to explore it in Richfest of CY 453. In CY 460, a journal purporting to be that of the expedition's magician, Henriki Ardand, surfaced in the Free City of Greyhawk. This text, whose veracity has not been confirmed, describes the group's journey to the vale and the extraordinary things they encountered there.
Rigodruok has been described as a green, fertile bowl about 30 miles in diameter, surrounded by a range of low mountains and a region of obfuscating mist. Half a mile over the center of the valley is a small sunlike body. Large islands of land float in the sky as well, some of them with small rivers that plummet over the edges, showering the valley with rainbows and moisture. Beneath the "sun" is a lake from which steam arises, surrounded by several clumps of broken and rusted towers of iron and glass.
Ecology and inhabitants
The fauna and sapients of the valley include goblins, bugbears, giant spiders of various sorts, and primitive cave-dwelling humans who evidently worship the spiders and their humanoid servants as gods.
Features and settlements
One human settlement includes large statues of spiders with valuable diamonds as eyes. An underground passage leads to the headwaters of the Fler River.
The whole valley is rich in diamonds, and a number of magical items can be found in the ruins or in the hands of the spiders and their alleys.
- Moore, Roger E. Greyhawk: The Adventure Begins. Renton, WA: Wizards of the Coast, 1998.
- -----. "Greyhawk Mysterious Places." Lake Geneva, WI: TSR, 1999. Originally appeared in TSR's America Online folder as a 2nd edition update to Greyhawk Adventures, later moved to its website. No longer live on the WotC website but available from the Wayback Machine: 
- -----. "The Orbs of Dragonkind." Dragon #230. Lake Geneva, WI: TSR, 1996.