the thing i was looking at was the page for the east wing of the white house because i saw someone saying "it had been there for decades before being destroyed" and i was like "i thought it was longer than that," and wikipedia tells a sort of three stage history: first there was just the side of the building, then they added stepped terraces with little collonade passages with washrooms, because i guess people would be arriving by horse/carriage or walking and would just be filthy. then they added a U shaped driveway that was mostly an entryway for dignitaries in 1902 shortly after the mass manufacture of cars began. then in WWII it ceased to be an entryway at all, sort of exactly the opposite, a bunker, to keep the out out rather than the in in.
and since i was also reading about some of the biblical wall fist shaking the other day it made me want to know more about the architectural/political history of approaches to buildings