Sorry for the quite ambiguous name for the thread, though, something has just occurred to me (please, correct me if I’m wrong but hear me out ahaa!)
It’s often been thought, through the Half-Life 1 story arc that there is no full map of the Black Mesa Research Facility (simply for the fact that Gordon is knocked unconscious and taken to another part of the facility), so the facility is separated into two distinct, large areas (as can be seen from the maps of Half-Life 1 currently available on Google, showing the separation).
However, I’ve been thinking long and hard about this.
In Opposing Force, near to the start of the game, Shephard crosses through the area on the tram system in which Gordon travels through, prior to arriving at Sector C (large area with leaking toxic waste and the robot).
However, if you follow Shephards’ travels, from this point, without blacking out, or any significant changes in level infrastructure, as Shephard, if I recall correctly you make it uninterrupted to the Lambda Complex, where you see Gordon jump in to the portal to Xen.
This, through level design, would link Sector C (prior to Gordon blacking out), to the Lambda Complex (after he has blacked out).
With some fancy software or a LOT of hard work, one could easily combine and piece all the maps from Half-Life, Opposing Force, and Blue Shift together, to create one definite map of the entirety of the Black Mesa facility, without that separation of not knowing where the two separate sections are in relation to one another. It truly would, show the facility as a whole, no matter how many ridiculously complex overlaps there may be in level geometry hahaa.
Something to think about anyway, correct me if I’m wrong, but an interesting concept nonetheless.