What the Helen of Troy is This

“Why do we have so many manholes in DC??”

“Dear PoPville,

I have wondered for years – Why do we have so many manholes in DC?? Please take a look at this street view with an egregious example – six in one intersection,

outside the soviet safeway. (If someone more clever than me wishes to make a joke about the choice of location here… by all means, in good taste.) But also – please tell me why??