The job of rebuilding vital infrastructure in and around Ground Zero began immediately after the nine months of relentless clean-up work was performed by unionized members of New York City's building and construction trades. In record time, workers rebuilt the 1/9 subway line that runs underneath the World Trade Center, reconnecting part of Lower Manhattan into the larger city subway network. As New York City continues to adjust and rebuild, this work plays an important role in the economic growth and revitalization of this devastated area. These images show the day-to-day work by union building trades members that is so important to the redevelopment of New York. Photography by Sam Hollenshead.