[5/17/2018 update: I decided to go back to this old post and flesh it out a little better.]
The purpose of this post is to share what I know about the development of the material from the early days of Dungeons & Dragons, up through the 1970s, to when they were eventually published adventure modules, and to build a timetable out of it. At one point, this included material that was never published, but that I knew about circa 2007. I know about a lot more know, but can refer readers to better sources for that, like the timeline on the Rob Kuntz Archive DVD.
1. Castle Blackmoor. Dave Arneson’s home campaign centers around Castle Blackmoor and later is released in the Judges Guild accessory The First Fantasy Campaign. The castle had 12 levels of dungeons. A town called Blackmoor, located outside the castle, provided support for the adventurers between expeditions, and also itself served as a backdrop for adventures (such as repelling invaders).
2. Castle Greyhawk. Inspired by Castle Blackmoor, Gary Gygax creates his own home campaign centered around a fantasy castle. The original Castle Greyhawk material has never been published, though details of it crept into the 1990 TSR module Greyhawk Ruins. The castle dungeons grew over time from 10 levels to a sprawling complex with an uncountable number of sub-levels, and even a slide that takes you all the way to the other side of the planet. Though unpublished, many details of the castle have been shared over the years and Allan Grohe has compiled them on his remarkable website.
3. El Raja Key. Rob Kuntz’s campaign, inspired by Castle Greyhawk, and would soon become sort of merged with Castle Greyhawk after the two become co-DMs. Parts of El Raja Key have been released over the years, most famously in the 1984 TSR module Mordenkainen's Fantastic Adventure. Many levels of El Raja Key are included, with original maps and keys, on the Rob Kuntz Archive DVD, though it appears to me that instead of the original keys these reflect a restocking of the dungeon that must have happened circa 1981.
4. City Greyhawk. The first full-sized fantasy city developed for a RPG (Blackmoor only had a town by it). TSR put out an amazing City of Greyhawk boxed set in 1989, but scant details of it bear any similarity to the original co-designed by Gygax and Kuntz. The original version of the city has never seen print, though more details of it can be gleaned from Gygax's Gord the Rogue novels.
5. Lost City of the Elders. From Rob Kuntz's home campaign. Part of the Lost City is known as the Garden of the Plant Master. Garden of the Plant Master was first published by Creations Unlimited in 1987, then by Kenzer & Company in 2003. The last known time Lost City was publicly run at GaryCon in 2012 and it then had sections allegedly challenging enough for 14th level characters.
6. Castle Glendower? This date is speculation. Glendower was another town in the Blackmoor campaign, this one with a four-level dungeon beneath it. Like Castle Greyhawk, the notes for it were published in The First Fantasy Campaign.
7. Loch Glomen/Lake Gloomey? Again, speculation. Lake Gloomey was a monster-infested area reachable from Blackmoor. Instead of underground dungeon, Glomen had areas above ground, like a mansion, that needed to be cleared out of monsters. Like Blackmoor and Glendower, the notes for Loch Glomen were published in The First Fantasy Campaign.
8. Temple of the Frog. The scenario was played first in the Blackmoor home campaign, but then was written up (and more than just in note form like the FFC material) and published in the 1975 TSR Supplement, Blackmoor. TSR published a revised and expanded version in 1986, and then was published again by Zeitgeist Games in 2007.
9. Tomb of Horrors. It is unclear if this was written first for Origins I in 1975 as one of the first D&D tournaments, or if it was played in the Greyhawk home campaign first -- but definitely one happened first and then the other. TSR published The Tomb of Horrors first in 1978 and it has been reprinted often since then.
10. The Stalk. An outdoor scenario from Kuntz's home campaign (Kalibruhn, where El Raja Key could be found) for characters of up to 12th level. Kuntz self-published it (as Pied Piper Publishing) in 2007.
11. Escape from Astigar’s Lair (MichiCon V tournament/JG module)
13. GENCON IX Dungeons (tournaments/JG module)
14. Lost Caverns of Tsojconth (WinterCon V tournament/Metro Detroit Games module/TSR module)
15. Palace of the Vampire Queen (Wee Warriors module)
16. Demonworld (R.K. campaign)
17. Dark Druids (R.K. campaign/Necromancer Games module)
18. Lair of the Pit Fiend (R.K. campaign)
19. Dwarven Glory (WW module)
20. City State of the Invincible Overlord (JG accessory)
21. Tegel Manor (JG module)
22. Modron (JG module)
23. Of Skulls and Scrapfaggot Green (GenCon X tournament/JG module)
24. Sample dungeon from Holmes ed. D&D Basic Rules
25. Steading of the Hill Giant Chief (TSR module)
26. Glacial Rift of the Frost Giant Jarl (TSR module)
27. Hall of the Fire Giant King (TSR module)
28. Descent Into the Depths of the Earth (TSR module)
29. Shrine of the Kuo-Toa (TSR module)
30. Vault of the Drow (TSR module)
31. Tomb of Horrors (TSR module)
32. The Thieves of Fortress Badabaskor (JG module)
33. Citadel of Fire (JG module)
34. Frontier Forts of Kelnore (JG module)
35. The Dragon Crown (JG module)
36. Quest for the Fazzlewood (WinterCon VII tournament/Metro Detroit Games module/TSR module)
37. The Village of Hommlet (TSR module)
38. White Plume Mountain (TSR module)
39. Pharoah (Day Star Media module/TSR module)
40. Rahasia (DSM module/TSR module)
41. Fortress Ellendar (Fantasy Productions module)
42. Lost Tomoachan: The Hidden Shrine of Lubaatum (Origins V tournament/TSR module)
43. The Ghost Tower of Inverness (WinterCon VIII tournament/TSR module)
44. Sample dungeon from AD&D Dungeon Master's Guide