These were posted by Hideo Kojima on Twitter about 13 years ago. The detailed maps were likely drawn by Kojima, since he has talked about making these maps himself. There are rumors of a "warehouse" where Konami keeps its old design documents from this era, but it's just hearsay.
Along with these design documents for Metal Gear, he also showed documents from Snatcher and Metal Gear 2: Solid Snake (there's 4 or 5 binders worth of documents for Snatcher, and maybe 1 or 2 for MG2). The MG2 and Policenauts binders were still on Kojima's desk in the late 90s.
The binders from the above photo can be seen in greater detail in the Metal Gear Solid reveal trailer from 1996. A few other shots of Kojima's desk and other areas of the KCEJ office can be seen as well.
