I have created a new map and posted it
here in the Image Gallery.
The map identifies all 44 of the District Doors with a unique ID number. For anyone who wishes to report findings related to a District Door, using the IDs provided in this map will allow everyone to understand exactly which door is meant.
I could have used an arbitrary assignment of numbers from 1-44, but I felt that the IDs should have an inherent meaning. To this end, each ID is comprised of the two district numbers which correspond to the two districts joined by the given district door. You'll see these same IDs in maps I made previously (e.g.
this map to show the location of Squidhenge.)
The IDs are in the format Dxxyy-z where xx and yy are district numbers indicating the districts on either side of the door ("ON" for ONI) and z is a letter between A and C which helps to make the ID unique in cases where multiple doors exist between the same two districts.
I assigned the numbers following a path through the city which approximates the "typical" path you might follow if you were playing campaign mode the way it was "intended" and described in the Prima Official Game Guide. In other words: D05,D08,D09,D06,D04,D10,ONI,D03,D00.
While making this map, I discovered a few points of interest:
There are two locked doors which lead into an undefined District above D05. This district would be a mirror image of D10. Although it may have been more logical to call this "District 11", I opted to give it the ID 99 since that was the last valid district number in my district door ID format- it also seemed presumptive to consider it District 11 since perhaps (if we're lucky!) such a District might exist with that number already! Therefore, there are two District Door IDs in D05 with the number 99 in them: D0599-A and D0299-A. You can tell right from the IDs that these doors are in Districts 05 and 02, respectively. District 02?!? Yes... you can see where the door would be in the dark area of District 02. You can also see how the shape of "District 99" mirrors the shape of District 10, the latter which contains two doors in the same orientation.
There are also two locked doors in the dark area of D09 which lead to a non-district (unknown) area and received the 99 treatment: D0999-A and D0999-B. These were added to the map 2009.12.12.
A third update on 2009.12.17 added six more doors into D99. D00 was updated with D0099-A and D0099-B which can be observed by bump glitching. The remaining four doors are theoretical. They should exist based on the presumption that the district they're marked in is a mirror image of a district in which they can be observed. In D07 I added D0799-A and D0799-B. These should exist based on the doors D0099-A and D0099-B. Finally, in D01 I added D0199-A and D0199-B. These should exist based on the doors D0999-A and D0999-B. With enough Black Ops work, it may be possible to observe these four theoretical doors.
The doors which lead from District 10 into ONI are different from the others: they bear the ONI logo and retract vertically rather than horizontally. I didn't bother to make the icons for these doors a different color since they are basically the same in function from the player's perspective. Only two of these doors are unlocked (the two that you always have to go though to get to ONI.) It's worth noting that the first door (D1010-A) doesn't actually connect to a different district... technically speaking. The tunnel that you travel through is part of the District 10 BSP. It isn't until you get to the second one (D10ON-A) that the final loading for the ONI area occurs. Indeed, you can bump D04 or D06 using the preload boundary in the tunnel, which is just inside of D1010-A. Had they constructed all of the district doors this way (with preload boundaries behind an initial door) then accidental bumping (and object despawning) would happen a lot less. Ah, well.
Please let me know if you find any errors with this first version of the map, and especially if you find any missing doors!