When F. Scott Fitzgerald was writing The Great Gatsby, 2nd Ave IRT trains still ran on the upper level of the Bridge.

The Bridge is still there, but New Yorkers are still waiting for the return of those 2nd Ave trains.

Sometimes one wonders why, “back in the day,” it was often possible to build things (like subway lines) in just a few years, when today it could take many decades to do the same work even with the vastly improved technologies that are now available.