ON THIS EDITION IT'S A LOOK AT THE VERY FIRST TRANSIT SYSTEM TO RUN THROUGH THE TUNNELS AND ELEVATED TRACKS THROUGH THE FIVE BOROUGHS, KNOWN AS THE INTERBOROUGH RAPID TRANSIT SYSTEM OR IRT: https://en.wikipedia.org/wiki/Early_history_of_the_IRT_subway Photo by: https://commons.wikimedia.org/wiki/File:1897_Poor%27s_Brooklyn_Rapid_Transit_Company.jpg