Easy Trivia

Easy: Name this structure:

Harder: How did this structure come to be?

Hardest: Name the street corner from which I took this picture.

You figure it out while I have some tea:
 

miles per gallon = litres per 100 kilometres

So I’m driving a Honda Civic Hybrid in Buffalo this weekend and it’s a nice car.  It’s not my Jetta, but it’s a nice car.  The interior dash does both US and metric measurements (digitally, might I add).  What I find unique is that when I push the button to go from US to metric, the mpg changes to l/100km.  The other thing is that in order for this inversion to work, the digital gage works in the opposite direction.

Trivia: Explain this to me: explain why it’s not km/l.  Also, explain to me why there’s no metric prefix for 100km.