59th Street Bridge (Queensborough Bridge) and Midtown Manhattan

In honor of the 30th anniversary of Simon and Garfunkel’s Central Park reunion concert, I ask the following question.  Why is their hit song Feelin’ Groovy also called The 59th Street Bridge Song?  Why???  Why name a song after that bridge? Any ideas? Is it because the view from the bridge is spectacular?  Or because they often went over that bridge? Or is it for no particular reason at all except that maybe one or both of them crossed the bridge when they were in an altered state of consciousness?  (How’s that for delicacy?)

This calls for more research. It makes me want to walk over the bridge to see for myself.  Sober.