"First Avenue Subway" (Route #1 from 1905)

The first route William Barclay Parsons (Chief Engineer of the Rapid Transit Commission) laid out while the IRT was under construction would have stretched from Claremont Park in the Bronx, run southwards to 1st Avenue, make a straight shot to the Lower East Side, and then weave it's way to the Financial District. His bosses at the Rapid Transit Commission (and it's successor, the Public Service Commission) considered the route worthwhile, but not crucial in the near term. The plan was put on the back burner with some southern stretches being adopted into the Board of Transportation's IND system in the 1930's. To this day there is no other subway line to supplement the IRT East Side (the Lex) as it runs through the dense east side of Manhattan north of Houston Street. Read more after the jump.

The 1905 vision of Manhattan and the Bronx

Long before the IND or BMT came into the picture—indeed literally at the dawn of subway building in New York—William Barclay Parsons was already engineering the encore to his "Rapid Transit Railroad" aka the Interborough Rapid Transit system, the first leg of our Subway system. Read more after the jump.

This map is from the "Railroad Gazette, 1907" posted online courtesy of Google Books.