One of the things that might not be obvious is besides being examples of 1970s concrete brutalism, the waffled arched ceilings in the Metro are meant to evoke t

One of the things that might not be obvious is besides being examples of 1970s concrete brutalism, the waffled arched ceilings in the Metro are meant to evoke the similar waffled ceiling of DC's historic Union Station (which in turn are a reference to ancient Roman architecture). So you can pretend you are living in a world where Rome didn't fall while waiting for a train (not sure if that's better than bad SF).